diff --git a/changelog.d/11851.misc b/changelog.d/11851.misc
new file mode 100644
index 000000000..ccc3ec348
--- /dev/null
+++ b/changelog.d/11851.misc
@@ -0,0 +1 @@
+Add type hints to `tests/rest/admin`.
diff --git a/mypy.ini b/mypy.ini
index 85fa22d28..2884078d0 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -77,9 +77,6 @@ exclude = (?x)
    |tests/push/test_http.py
    |tests/push/test_presentable_names.py
    |tests/push/test_push_rule_evaluator.py
-   |tests/rest/admin/test_admin.py
-   |tests/rest/admin/test_user.py
-   |tests/rest/admin/test_username_available.py
    |tests/rest/client/test_account.py
    |tests/rest/client/test_events.py
    |tests/rest/client/test_filter.py
diff --git a/tests/rest/admin/test_admin.py b/tests/rest/admin/test_admin.py
index 3adadcb46..849d00ab4 100644
--- a/tests/rest/admin/test_admin.py
+++ b/tests/rest/admin/test_admin.py
@@ -12,18 +12,20 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import os
 import urllib.parse
 from http import HTTPStatus
-from unittest.mock import Mock
+from typing import List
 
-from twisted.internet.defer import Deferred
+from parameterized import parameterized
+
+from twisted.test.proto_helpers import MemoryReactor
 
 import synapse.rest.admin
 from synapse.http.server import JsonResource
-from synapse.logging.context import make_deferred_yieldable
 from synapse.rest.admin import VersionServlet
 from synapse.rest.client import groups, login, room
+from synapse.server import HomeServer
+from synapse.util import Clock
 
 from tests import unittest
 from tests.server import FakeSite, make_request
@@ -33,12 +35,12 @@ from tests.test_utils import SMALL_PNG
 class VersionTestCase(unittest.HomeserverTestCase):
     url = "/_synapse/admin/v1/server_version"
 
-    def create_test_resource(self):
+    def create_test_resource(self) -> JsonResource:
         resource = JsonResource(self.hs)
         VersionServlet(self.hs).register(resource)
         return resource
 
-    def test_version_string(self):
+    def test_version_string(self) -> None:
         channel = self.make_request("GET", self.url, shorthand=False)
 
         self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
@@ -54,14 +56,14 @@ class DeleteGroupTestCase(unittest.HomeserverTestCase):
         groups.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.admin_user = self.register_user("admin", "pass", admin=True)
         self.admin_user_tok = self.login("admin", "pass")
 
         self.other_user = self.register_user("user", "pass")
         self.other_user_token = self.login("user", "pass")
 
-    def test_delete_group(self):
+    def test_delete_group(self) -> None:
         # Create a new group
         channel = self.make_request(
             "POST",
@@ -112,7 +114,7 @@ class DeleteGroupTestCase(unittest.HomeserverTestCase):
         self.assertNotIn(group_id, self._get_groups_user_is_in(self.admin_user_tok))
         self.assertNotIn(group_id, self._get_groups_user_is_in(self.other_user_token))
 
-    def _check_group(self, group_id, expect_code):
+    def _check_group(self, group_id: str, expect_code: int) -> None:
         """Assert that trying to fetch the given group results in the given
         HTTP status code
         """
@@ -124,7 +126,7 @@ class DeleteGroupTestCase(unittest.HomeserverTestCase):
 
         self.assertEqual(expect_code, channel.code, msg=channel.json_body)
 
-    def _get_groups_user_is_in(self, access_token):
+    def _get_groups_user_is_in(self, access_token: str) -> List[str]:
         """Returns the list of groups the user is in (given their access token)"""
         channel = self.make_request("GET", b"/joined_groups", access_token=access_token)
 
@@ -143,59 +145,15 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
         room.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         # Allow for uploading and downloading to/from the media repo
         self.media_repo = hs.get_media_repository_resource()
         self.download_resource = self.media_repo.children[b"download"]
         self.upload_resource = self.media_repo.children[b"upload"]
 
-    def make_homeserver(self, reactor, clock):
-
-        self.fetches = []
-
-        async def get_file(destination, path, output_stream, args=None, max_size=None):
-            """
-            Returns tuple[int,dict,str,int] of file length, response headers,
-            absolute URI, and response code.
-            """
-
-            def write_to(r):
-                data, response = r
-                output_stream.write(data)
-                return response
-
-            d = Deferred()
-            d.addCallback(write_to)
-            self.fetches.append((d, destination, path, args))
-            return await make_deferred_yieldable(d)
-
-        client = Mock()
-        client.get_file = get_file
-
-        self.storage_path = self.mktemp()
-        self.media_store_path = self.mktemp()
-        os.mkdir(self.storage_path)
-        os.mkdir(self.media_store_path)
-
-        config = self.default_config()
-        config["media_store_path"] = self.media_store_path
-        config["thumbnail_requirements"] = {}
-        config["max_image_pixels"] = 2000000
-
-        provider_config = {
-            "module": "synapse.rest.media.v1.storage_provider.FileStorageProviderBackend",
-            "store_local": True,
-            "store_synchronous": False,
-            "store_remote": True,
-            "config": {"directory": self.storage_path},
-        }
-        config["media_storage_providers"] = [provider_config]
-
-        hs = self.setup_test_homeserver(config=config, federation_http_client=client)
-
-        return hs
-
-    def _ensure_quarantined(self, admin_user_tok, server_and_media_id):
+    def _ensure_quarantined(
+        self, admin_user_tok: str, server_and_media_id: str
+    ) -> None:
         """Ensure a piece of media is quarantined when trying to access it."""
         channel = make_request(
             self.reactor,
@@ -216,12 +174,18 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
             ),
         )
 
-    def test_quarantine_media_requires_admin(self):
+    @parameterized.expand(
+        [
+            # Attempt quarantine media APIs as non-admin
+            "/_synapse/admin/v1/media/quarantine/example.org/abcde12345",
+            # And the roomID/userID endpoint
+            "/_synapse/admin/v1/room/!room%3Aexample.com/media/quarantine",
+        ]
+    )
+    def test_quarantine_media_requires_admin(self, url: str) -> None:
         self.register_user("nonadmin", "pass", admin=False)
         non_admin_user_tok = self.login("nonadmin", "pass")
 
-        # Attempt quarantine media APIs as non-admin
-        url = "/_synapse/admin/v1/media/quarantine/example.org/abcde12345"
         channel = self.make_request(
             "POST",
             url.encode("ascii"),
@@ -235,22 +199,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
             msg="Expected forbidden on quarantining media as a non-admin",
         )
 
-        # And the roomID/userID endpoint
-        url = "/_synapse/admin/v1/room/!room%3Aexample.com/media/quarantine"
-        channel = self.make_request(
-            "POST",
-            url.encode("ascii"),
-            access_token=non_admin_user_tok,
-        )
-
-        # Expect a forbidden error
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg="Expected forbidden on quarantining media as a non-admin",
-        )
-
-    def test_quarantine_media_by_id(self):
+    def test_quarantine_media_by_id(self) -> None:
         self.register_user("id_admin", "pass", admin=True)
         admin_user_tok = self.login("id_admin", "pass")
 
@@ -295,7 +244,15 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
         # Attempt to access the media
         self._ensure_quarantined(admin_user_tok, server_name_and_media_id)
 
-    def test_quarantine_all_media_in_room(self, override_url_template=None):
+    @parameterized.expand(
+        [
+            # regular API path
+            "/_synapse/admin/v1/room/%s/media/quarantine",
+            # deprecated API path
+            "/_synapse/admin/v1/quarantine_media/%s",
+        ]
+    )
+    def test_quarantine_all_media_in_room(self, url: str) -> None:
         self.register_user("room_admin", "pass", admin=True)
         admin_user_tok = self.login("room_admin", "pass")
 
@@ -333,16 +290,9 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
             tok=non_admin_user_tok,
         )
 
-        # Quarantine all media in the room
-        if override_url_template:
-            url = override_url_template % urllib.parse.quote(room_id)
-        else:
-            url = "/_synapse/admin/v1/room/%s/media/quarantine" % urllib.parse.quote(
-                room_id
-            )
         channel = self.make_request(
             "POST",
-            url,
+            url % urllib.parse.quote(room_id),
             access_token=admin_user_tok,
         )
         self.pump(1.0)
@@ -359,11 +309,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
         self._ensure_quarantined(admin_user_tok, server_and_media_id_1)
         self._ensure_quarantined(admin_user_tok, server_and_media_id_2)
 
-    def test_quarantine_all_media_in_room_deprecated_api_path(self):
-        # Perform the above test with the deprecated API path
-        self.test_quarantine_all_media_in_room("/_synapse/admin/v1/quarantine_media/%s")
-
-    def test_quarantine_all_media_by_user(self):
+    def test_quarantine_all_media_by_user(self) -> None:
         self.register_user("user_admin", "pass", admin=True)
         admin_user_tok = self.login("user_admin", "pass")
 
@@ -401,7 +347,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
         self._ensure_quarantined(admin_user_tok, server_and_media_id_1)
         self._ensure_quarantined(admin_user_tok, server_and_media_id_2)
 
-    def test_cannot_quarantine_safe_media(self):
+    def test_cannot_quarantine_safe_media(self) -> None:
         self.register_user("user_admin", "pass", admin=True)
         admin_user_tok = self.login("user_admin", "pass")
 
@@ -475,7 +421,7 @@ class PurgeHistoryTestCase(unittest.HomeserverTestCase):
         room.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.admin_user = self.register_user("admin", "pass", admin=True)
         self.admin_user_tok = self.login("admin", "pass")
 
@@ -488,7 +434,7 @@ class PurgeHistoryTestCase(unittest.HomeserverTestCase):
         self.url = f"/_synapse/admin/v1/purge_history/{self.room_id}"
         self.url_status = "/_synapse/admin/v1/purge_history_status/"
 
-    def test_purge_history(self):
+    def test_purge_history(self) -> None:
         """
         Simple test of purge history API.
         Test only that is is possible to call, get status HTTPStatus.OK and purge_id.
diff --git a/tests/rest/admin/test_user.py b/tests/rest/admin/test_user.py
index 971140573..272637e96 100644
--- a/tests/rest/admin/test_user.py
+++ b/tests/rest/admin/test_user.py
@@ -23,13 +23,17 @@ from unittest.mock import Mock, patch
 
 from parameterized import parameterized, parameterized_class
 
+from twisted.test.proto_helpers import MemoryReactor
+
 import synapse.rest.admin
 from synapse.api.constants import UserTypes
 from synapse.api.errors import Codes, HttpResponseException, ResourceLimitError
 from synapse.api.room_versions import RoomVersions
 from synapse.rest.client import devices, login, logout, profile, room, sync
 from synapse.rest.media.v1.filepath import MediaFilePaths
+from synapse.server import HomeServer
 from synapse.types import JsonDict, UserID
+from synapse.util import Clock
 
 from tests import unittest
 from tests.server import FakeSite, make_request
@@ -44,7 +48,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         profile.register_servlets,
     ]
 
-    def make_homeserver(self, reactor, clock):
+    def make_homeserver(self, reactor: MemoryReactor, clock: Clock) -> HomeServer:
 
         self.url = "/_synapse/admin/v1/register"
 
@@ -61,12 +65,12 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
 
         self.hs.config.registration.registration_shared_secret = "shared"
 
-        self.hs.get_media_repository = Mock()
-        self.hs.get_deactivate_account_handler = Mock()
+        self.hs.get_media_repository = Mock()  # type: ignore[assignment]
+        self.hs.get_deactivate_account_handler = Mock()  # type: ignore[assignment]
 
         return self.hs
 
-    def test_disabled(self):
+    def test_disabled(self) -> None:
         """
         If there is no shared secret, registration through this method will be
         prevented.
@@ -80,7 +84,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
             "Shared secret registration is not enabled", channel.json_body["error"]
         )
 
-    def test_get_nonce(self):
+    def test_get_nonce(self) -> None:
         """
         Calling GET on the endpoint will return a randomised nonce, using the
         homeserver's secrets provider.
@@ -93,7 +97,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
 
             self.assertEqual(channel.json_body, {"nonce": "abcd"})
 
-    def test_expired_nonce(self):
+    def test_expired_nonce(self) -> None:
         """
         Calling GET on the endpoint will return a randomised nonce, which will
         only last for SALT_TIMEOUT (60s).
@@ -118,7 +122,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual("unrecognised nonce", channel.json_body["error"])
 
-    def test_register_incorrect_nonce(self):
+    def test_register_incorrect_nonce(self) -> None:
         """
         Only the provided nonce can be used, as it's checked in the MAC.
         """
@@ -141,7 +145,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
         self.assertEqual("HMAC incorrect", channel.json_body["error"])
 
-    def test_register_correct_nonce(self):
+    def test_register_correct_nonce(self) -> None:
         """
         When the correct nonce is provided, and the right key is provided, the
         user is registered.
@@ -168,7 +172,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["user_id"])
 
-    def test_nonce_reuse(self):
+    def test_nonce_reuse(self) -> None:
         """
         A valid unrecognised nonce.
         """
@@ -197,14 +201,14 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual("unrecognised nonce", channel.json_body["error"])
 
-    def test_missing_parts(self):
+    def test_missing_parts(self) -> None:
         """
         Synapse will complain if you don't give nonce, username, password, and
         mac.  Admin and user_types are optional.  Additional checks are done for length
         and type.
         """
 
-        def nonce():
+        def nonce() -> str:
             channel = self.make_request("GET", self.url)
             return channel.json_body["nonce"]
 
@@ -297,7 +301,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual("Invalid user type", channel.json_body["error"])
 
-    def test_displayname(self):
+    def test_displayname(self) -> None:
         """
         Test that displayname of new user is set
         """
@@ -400,7 +404,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
     @override_config(
         {"limit_usage_by_mau": True, "max_mau_value": 2, "mau_trial_days": 0}
     )
-    def test_register_mau_limit_reached(self):
+    def test_register_mau_limit_reached(self) -> None:
         """
         Check we can register a user via the shared secret registration API
         even if the MAU limit is reached.
@@ -450,13 +454,13 @@ class UsersListTestCase(unittest.HomeserverTestCase):
     ]
     url = "/_synapse/admin/v2/users"
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = hs.get_datastore()
 
         self.admin_user = self.register_user("admin", "pass", admin=True)
         self.admin_user_tok = self.login("admin", "pass")
 
-    def test_no_auth(self):
+    def test_no_auth(self) -> None:
         """
         Try to list users without authentication.
         """
@@ -465,7 +469,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
-    def test_requester_is_no_admin(self):
+    def test_requester_is_no_admin(self) -> None:
         """
         If the user is not a server admin, an error is returned.
         """
@@ -477,7 +481,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
-    def test_all_users(self):
+    def test_all_users(self) -> None:
         """
         List all users, including deactivated users.
         """
@@ -497,7 +501,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         # Check that all fields are available
         self._check_fields(channel.json_body["users"])
 
-    def test_search_term(self):
+    def test_search_term(self) -> None:
         """Test that searching for a users works correctly"""
 
         def _search_test(
@@ -505,7 +509,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             search_term: str,
             search_field: Optional[str] = "name",
             expected_http_code: Optional[int] = HTTPStatus.OK,
-        ):
+        ) -> None:
             """Search for a user and check that the returned user's id is a match
 
             Args:
@@ -575,7 +579,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         _search_test(None, "foo", "user_id")
         _search_test(None, "bar", "user_id")
 
-    def test_invalid_parameter(self):
+    def test_invalid_parameter(self) -> None:
         """
         If parameters are invalid, an error is returned.
         """
@@ -640,7 +644,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
-    def test_limit(self):
+    def test_limit(self) -> None:
         """
         Testing list of users with limit
         """
@@ -661,7 +665,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         self.assertEqual(channel.json_body["next_token"], "5")
         self._check_fields(channel.json_body["users"])
 
-    def test_from(self):
+    def test_from(self) -> None:
         """
         Testing list of users with a defined starting point (from)
         """
@@ -682,7 +686,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         self.assertNotIn("next_token", channel.json_body)
         self._check_fields(channel.json_body["users"])
 
-    def test_limit_and_from(self):
+    def test_limit_and_from(self) -> None:
         """
         Testing list of users with a defined starting point and limit
         """
@@ -703,7 +707,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         self.assertEqual(len(channel.json_body["users"]), 10)
         self._check_fields(channel.json_body["users"])
 
-    def test_next_token(self):
+    def test_next_token(self) -> None:
         """
         Testing that `next_token` appears at the right place
         """
@@ -765,7 +769,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         self.assertEqual(len(channel.json_body["users"]), 1)
         self.assertNotIn("next_token", channel.json_body)
 
-    def test_order_by(self):
+    def test_order_by(self) -> None:
         """
         Testing order list with parameter `order_by`
         """
@@ -843,7 +847,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         expected_user_list: List[str],
         order_by: Optional[str],
         dir: Optional[str] = None,
-    ):
+    ) -> None:
         """Request the list of users in a certain order. Assert that order is what
         we expect
         Args:
@@ -870,7 +874,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         self.assertEqual(expected_user_list, returned_order)
         self._check_fields(channel.json_body["users"])
 
-    def _check_fields(self, content: List[JsonDict]):
+    def _check_fields(self, content: List[JsonDict]) -> None:
         """Checks that the expected user attributes are present in content
         Args:
             content: List that is checked for content
@@ -886,7 +890,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             self.assertIn("avatar_url", u)
             self.assertIn("creation_ts", u)
 
-    def _create_users(self, number_users: int):
+    def _create_users(self, number_users: int) -> None:
         """
         Create a number of users
         Args:
@@ -908,7 +912,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
         login.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = hs.get_datastore()
 
         self.admin_user = self.register_user("admin", "pass", admin=True)
@@ -931,7 +935,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             self.store.user_add_threepid("@user:test", "email", "foo@bar.com", 0, 0)
         )
 
-    def test_no_auth(self):
+    def test_no_auth(self) -> None:
         """
         Try to deactivate users without authentication.
         """
@@ -940,7 +944,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
-    def test_requester_is_not_admin(self):
+    def test_requester_is_not_admin(self) -> None:
         """
         If the user is not a server admin, an error is returned.
         """
@@ -961,7 +965,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
         self.assertEqual("You are not a server admin", channel.json_body["error"])
 
-    def test_user_does_not_exist(self):
+    def test_user_does_not_exist(self) -> None:
         """
         Tests that deactivation for a user that does not exist returns a HTTPStatus.NOT_FOUND
         """
@@ -975,7 +979,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
-    def test_erase_is_not_bool(self):
+    def test_erase_is_not_bool(self) -> None:
         """
         If parameter `erase` is not boolean, return an error
         """
@@ -990,7 +994,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.BAD_JSON, channel.json_body["errcode"])
 
-    def test_user_is_not_local(self):
+    def test_user_is_not_local(self) -> None:
         """
         Tests that deactivation for a user that is not a local returns a HTTPStatus.BAD_REQUEST
         """
@@ -1001,7 +1005,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual("Can only deactivate local users", channel.json_body["error"])
 
-    def test_deactivate_user_erase_true(self):
+    def test_deactivate_user_erase_true(self) -> None:
         """
         Test deactivating a user and set `erase` to `true`
         """
@@ -1046,7 +1050,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
 
         self._is_erased("@user:test", True)
 
-    def test_deactivate_user_erase_false(self):
+    def test_deactivate_user_erase_false(self) -> None:
         """
         Test deactivating a user and set `erase` to `false`
         """
@@ -1091,7 +1095,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
 
         self._is_erased("@user:test", False)
 
-    def test_deactivate_user_erase_true_no_profile(self):
+    def test_deactivate_user_erase_true_no_profile(self) -> None:
         """
         Test deactivating a user and set `erase` to `true`
         if user has no profile information (stored in the database table `profiles`).
@@ -1162,7 +1166,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         sync.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = hs.get_datastore()
         self.auth_handler = hs.get_auth_handler()
 
@@ -1185,7 +1189,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.url_prefix = "/_synapse/admin/v2/users/%s"
         self.url_other_user = self.url_prefix % self.other_user
 
-    def test_requester_is_no_admin(self):
+    def test_requester_is_no_admin(self) -> None:
         """
         If the user is not a server admin, an error is returned.
         """
@@ -1210,7 +1214,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
         self.assertEqual("You are not a server admin", channel.json_body["error"])
 
-    def test_user_does_not_exist(self):
+    def test_user_does_not_exist(self) -> None:
         """
         Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
         """
@@ -1224,7 +1228,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
         self.assertEqual("M_NOT_FOUND", channel.json_body["errcode"])
 
-    def test_invalid_parameter(self):
+    def test_invalid_parameter(self) -> None:
         """
         If parameters are invalid, an error is returned.
         """
@@ -1319,7 +1323,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
 
-    def test_get_user(self):
+    def test_get_user(self) -> None:
         """
         Test a simple get of a user.
         """
@@ -1334,7 +1338,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual("User", channel.json_body["displayname"])
         self._check_fields(channel.json_body)
 
-    def test_create_server_admin(self):
+    def test_create_server_admin(self) -> None:
         """
         Check that a new admin user is created successfully.
         """
@@ -1383,7 +1387,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual("mxc://fibble/wibble", channel.json_body["avatar_url"])
         self._check_fields(channel.json_body)
 
-    def test_create_user(self):
+    def test_create_user(self) -> None:
         """
         Check that a new regular user is created successfully.
         """
@@ -1450,7 +1454,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
     @override_config(
         {"limit_usage_by_mau": True, "max_mau_value": 2, "mau_trial_days": 0}
     )
-    def test_create_user_mau_limit_reached_active_admin(self):
+    def test_create_user_mau_limit_reached_active_admin(self) -> None:
         """
         Check that an admin can register a new user via the admin API
         even if the MAU limit is reached.
@@ -1496,7 +1500,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
     @override_config(
         {"limit_usage_by_mau": True, "max_mau_value": 2, "mau_trial_days": 0}
     )
-    def test_create_user_mau_limit_reached_passive_admin(self):
+    def test_create_user_mau_limit_reached_passive_admin(self) -> None:
         """
         Check that an admin can register a new user via the admin API
         even if the MAU limit is reached.
@@ -1541,7 +1545,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             "public_baseurl": "https://example.com",
         }
     )
-    def test_create_user_email_notif_for_new_users(self):
+    def test_create_user_email_notif_for_new_users(self) -> None:
         """
         Check that a new regular user is created successfully and
         got an email pusher.
@@ -1584,7 +1588,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             "public_baseurl": "https://example.com",
         }
     )
-    def test_create_user_email_no_notif_for_new_users(self):
+    def test_create_user_email_no_notif_for_new_users(self) -> None:
         """
         Check that a new regular user is created successfully and
         got not an email pusher.
@@ -1615,7 +1619,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         pushers = list(pushers)
         self.assertEqual(len(pushers), 0)
 
-    def test_set_password(self):
+    def test_set_password(self) -> None:
         """
         Test setting a new password for another user.
         """
@@ -1631,7 +1635,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
         self._check_fields(channel.json_body)
 
-    def test_set_displayname(self):
+    def test_set_displayname(self) -> None:
         """
         Test setting the displayname of another user.
         """
@@ -1659,7 +1663,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual("foobar", channel.json_body["displayname"])
 
-    def test_set_threepid(self):
+    def test_set_threepid(self) -> None:
         """
         Test setting threepid for an other user.
         """
@@ -1740,7 +1744,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(0, len(channel.json_body["threepids"]))
         self._check_fields(channel.json_body)
 
-    def test_set_duplicate_threepid(self):
+    def test_set_duplicate_threepid(self) -> None:
         """
         Test setting the same threepid for a second user.
         First user loses and second user gets mapping of this threepid.
@@ -1827,7 +1831,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(0, len(channel.json_body["threepids"]))
         self._check_fields(channel.json_body)
 
-    def test_set_external_id(self):
+    def test_set_external_id(self) -> None:
         """
         Test setting external id for an other user.
         """
@@ -1925,7 +1929,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(0, len(channel.json_body["external_ids"]))
 
-    def test_set_duplicate_external_id(self):
+    def test_set_duplicate_external_id(self) -> None:
         """
         Test that setting the same external id for a second user fails and
         external id from user must not be changed.
@@ -2048,7 +2052,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         )
         self._check_fields(channel.json_body)
 
-    def test_deactivate_user(self):
+    def test_deactivate_user(self) -> None:
         """
         Test deactivating another user.
         """
@@ -2113,7 +2117,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertNotIn("password_hash", channel.json_body)
 
     @override_config({"user_directory": {"enabled": True, "search_all_users": True}})
-    def test_change_name_deactivate_user_user_directory(self):
+    def test_change_name_deactivate_user_user_directory(self) -> None:
         """
         Test change profile information of a deactivated user and
         check that it does not appear in user directory
@@ -2156,7 +2160,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         profile = self.get_success(self.store.get_user_in_directory(self.other_user))
         self.assertIsNone(profile)
 
-    def test_reactivate_user(self):
+    def test_reactivate_user(self) -> None:
         """
         Test reactivating another user.
         """
@@ -2189,7 +2193,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertNotIn("password_hash", channel.json_body)
 
     @override_config({"password_config": {"localdb_enabled": False}})
-    def test_reactivate_user_localdb_disabled(self):
+    def test_reactivate_user_localdb_disabled(self) -> None:
         """
         Test reactivating another user when using SSO.
         """
@@ -2223,7 +2227,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertNotIn("password_hash", channel.json_body)
 
     @override_config({"password_config": {"enabled": False}})
-    def test_reactivate_user_password_disabled(self):
+    def test_reactivate_user_password_disabled(self) -> None:
         """
         Test reactivating another user when using SSO.
         """
@@ -2256,7 +2260,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         # This key was removed intentionally. Ensure it is not accidentally re-included.
         self.assertNotIn("password_hash", channel.json_body)
 
-    def test_set_user_as_admin(self):
+    def test_set_user_as_admin(self) -> None:
         """
         Test setting the admin flag on a user.
         """
@@ -2284,7 +2288,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertTrue(channel.json_body["admin"])
 
-    def test_set_user_type(self):
+    def test_set_user_type(self) -> None:
         """
         Test changing user type.
         """
@@ -2335,7 +2339,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertIsNone(channel.json_body["user_type"])
 
-    def test_accidental_deactivation_prevention(self):
+    def test_accidental_deactivation_prevention(self) -> None:
         """
         Ensure an account can't accidentally be deactivated by using a str value
         for the deactivated body parameter
@@ -2418,7 +2422,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         # This key was removed intentionally. Ensure it is not accidentally re-included.
         self.assertNotIn("password_hash", channel.json_body)
 
-    def _check_fields(self, content: JsonDict):
+    def _check_fields(self, content: JsonDict) -> None:
         """Checks that the expected user attributes are present in content
 
         Args:
@@ -2448,7 +2452,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
         room.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.admin_user = self.register_user("admin", "pass", admin=True)
         self.admin_user_tok = self.login("admin", "pass")
 
@@ -2457,7 +2461,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
             self.other_user
         )
 
-    def test_no_auth(self):
+    def test_no_auth(self) -> None:
         """
         Try to list rooms of an user without authentication.
         """
@@ -2466,7 +2470,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
-    def test_requester_is_no_admin(self):
+    def test_requester_is_no_admin(self) -> None:
         """
         If the user is not a server admin, an error is returned.
         """
@@ -2481,7 +2485,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
-    def test_user_does_not_exist(self):
+    def test_user_does_not_exist(self) -> None:
         """
         Tests that a lookup for a user that does not exist returns an empty list
         """
@@ -2496,7 +2500,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["joined_rooms"]))
 
-    def test_user_is_not_local(self):
+    def test_user_is_not_local(self) -> None:
         """
         Tests that a lookup for a user that is not a local and participates in no conversation returns an empty list
         """
@@ -2512,7 +2516,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["joined_rooms"]))
 
-    def test_no_memberships(self):
+    def test_no_memberships(self) -> None:
         """
         Tests that a normal lookup for rooms is successfully
         if user has no memberships
@@ -2528,7 +2532,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["joined_rooms"]))
 
-    def test_get_rooms(self):
+    def test_get_rooms(self) -> None:
         """
         Tests that a normal lookup for rooms is successfully
         """
@@ -2549,7 +2553,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(number_rooms, channel.json_body["total"])
         self.assertEqual(number_rooms, len(channel.json_body["joined_rooms"]))
 
-    def test_get_rooms_with_nonlocal_user(self):
+    def test_get_rooms_with_nonlocal_user(self) -> None:
         """
         Tests that a normal lookup for rooms is successful with a non-local user
         """
@@ -2604,7 +2608,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
         login.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = hs.get_datastore()
 
         self.admin_user = self.register_user("admin", "pass", admin=True)
@@ -2615,7 +2619,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
             self.other_user
         )
 
-    def test_no_auth(self):
+    def test_no_auth(self) -> None:
         """
         Try to list pushers of an user without authentication.
         """
@@ -2624,7 +2628,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
-    def test_requester_is_no_admin(self):
+    def test_requester_is_no_admin(self) -> None:
         """
         If the user is not a server admin, an error is returned.
         """
@@ -2639,7 +2643,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
-    def test_user_does_not_exist(self):
+    def test_user_does_not_exist(self) -> None:
         """
         Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
         """
@@ -2653,7 +2657,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
-    def test_user_is_not_local(self):
+    def test_user_is_not_local(self) -> None:
         """
         Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
         """
@@ -2668,7 +2672,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual("Can only look up local users", channel.json_body["error"])
 
-    def test_get_pushers(self):
+    def test_get_pushers(self) -> None:
         """
         Tests that a normal lookup for pushers is successfully
         """
@@ -2732,7 +2736,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         login.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = hs.get_datastore()
         self.media_repo = hs.get_media_repository_resource()
         self.filepaths = MediaFilePaths(hs.config.media.media_store_path)
@@ -2746,7 +2750,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         )
 
     @parameterized.expand(["GET", "DELETE"])
-    def test_no_auth(self, method: str):
+    def test_no_auth(self, method: str) -> None:
         """Try to list media of an user without authentication."""
         channel = self.make_request(method, self.url, {})
 
@@ -2754,7 +2758,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "DELETE"])
-    def test_requester_is_no_admin(self, method: str):
+    def test_requester_is_no_admin(self, method: str) -> None:
         """If the user is not a server admin, an error is returned."""
         other_user_token = self.login("user", "pass")
 
@@ -2768,7 +2772,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "DELETE"])
-    def test_user_does_not_exist(self, method: str):
+    def test_user_does_not_exist(self, method: str) -> None:
         """Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND"""
         url = "/_synapse/admin/v1/users/@unknown_person:test/media"
         channel = self.make_request(
@@ -2781,7 +2785,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "DELETE"])
-    def test_user_is_not_local(self, method: str):
+    def test_user_is_not_local(self, method: str) -> None:
         """Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST"""
         url = "/_synapse/admin/v1/users/@unknown_person:unknown_domain/media"
 
@@ -2794,7 +2798,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual("Can only look up local users", channel.json_body["error"])
 
-    def test_limit_GET(self):
+    def test_limit_GET(self) -> None:
         """Testing list of media with limit"""
 
         number_media = 20
@@ -2813,7 +2817,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(channel.json_body["next_token"], 5)
         self._check_fields(channel.json_body["media"])
 
-    def test_limit_DELETE(self):
+    def test_limit_DELETE(self) -> None:
         """Testing delete of media with limit"""
 
         number_media = 20
@@ -2830,7 +2834,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(channel.json_body["total"], 5)
         self.assertEqual(len(channel.json_body["deleted_media"]), 5)
 
-    def test_from_GET(self):
+    def test_from_GET(self) -> None:
         """Testing list of media with a defined starting point (from)"""
 
         number_media = 20
@@ -2849,7 +2853,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertNotIn("next_token", channel.json_body)
         self._check_fields(channel.json_body["media"])
 
-    def test_from_DELETE(self):
+    def test_from_DELETE(self) -> None:
         """Testing delete of media with a defined starting point (from)"""
 
         number_media = 20
@@ -2866,7 +2870,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(channel.json_body["total"], 15)
         self.assertEqual(len(channel.json_body["deleted_media"]), 15)
 
-    def test_limit_and_from_GET(self):
+    def test_limit_and_from_GET(self) -> None:
         """Testing list of media with a defined starting point and limit"""
 
         number_media = 20
@@ -2885,7 +2889,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(len(channel.json_body["media"]), 10)
         self._check_fields(channel.json_body["media"])
 
-    def test_limit_and_from_DELETE(self):
+    def test_limit_and_from_DELETE(self) -> None:
         """Testing delete of media with a defined starting point and limit"""
 
         number_media = 20
@@ -2903,7 +2907,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(len(channel.json_body["deleted_media"]), 10)
 
     @parameterized.expand(["GET", "DELETE"])
-    def test_invalid_parameter(self, method: str):
+    def test_invalid_parameter(self, method: str) -> None:
         """If parameters are invalid, an error is returned."""
         # unkown order_by
         channel = self.make_request(
@@ -2945,7 +2949,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
-    def test_next_token(self):
+    def test_next_token(self) -> None:
         """
         Testing that `next_token` appears at the right place
 
@@ -3010,7 +3014,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(len(channel.json_body["media"]), 1)
         self.assertNotIn("next_token", channel.json_body)
 
-    def test_user_has_no_media_GET(self):
+    def test_user_has_no_media_GET(self) -> None:
         """
         Tests that a normal lookup for media is successfully
         if user has no media created
@@ -3026,7 +3030,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["media"]))
 
-    def test_user_has_no_media_DELETE(self):
+    def test_user_has_no_media_DELETE(self) -> None:
         """
         Tests that a delete is successful if user has no media
         """
@@ -3041,7 +3045,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["deleted_media"]))
 
-    def test_get_media(self):
+    def test_get_media(self) -> None:
         """Tests that a normal lookup for media is successful"""
 
         number_media = 5
@@ -3060,7 +3064,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         self.assertNotIn("next_token", channel.json_body)
         self._check_fields(channel.json_body["media"])
 
-    def test_delete_media(self):
+    def test_delete_media(self) -> None:
         """Tests that a normal delete of media is successful"""
 
         number_media = 5
@@ -3089,7 +3093,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         for local_path in local_paths:
             self.assertFalse(os.path.exists(local_path))
 
-    def test_order_by(self):
+    def test_order_by(self) -> None:
         """
         Testing order list with parameter `order_by`
         """
@@ -3252,7 +3256,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
 
         return media_id
 
-    def _check_fields(self, content: List[JsonDict]):
+    def _check_fields(self, content: List[JsonDict]) -> None:
         """Checks that the expected user attributes are present in content
         Args:
             content: List that is checked for content
@@ -3272,7 +3276,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         expected_media_list: List[str],
         order_by: Optional[str],
         dir: Optional[str] = None,
-    ):
+    ) -> None:
         """Request the list of media in a certain order. Assert that order is what
         we expect
         Args:
@@ -3312,7 +3316,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         logout.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = hs.get_datastore()
 
         self.admin_user = self.register_user("admin", "pass", admin=True)
@@ -3331,14 +3335,14 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
         return channel.json_body["access_token"]
 
-    def test_no_auth(self):
+    def test_no_auth(self) -> None:
         """Try to login as a user without authentication."""
         channel = self.make_request("POST", self.url, b"{}")
 
         self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
-    def test_not_admin(self):
+    def test_not_admin(self) -> None:
         """Try to login as a user as a non-admin user."""
         channel = self.make_request(
             "POST", self.url, b"{}", access_token=self.other_user_tok
@@ -3346,7 +3350,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
 
         self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
 
-    def test_send_event(self):
+    def test_send_event(self) -> None:
         """Test that sending event as a user works."""
         # Create a room.
         room_id = self.helper.create_room_as(self.other_user, tok=self.other_user_tok)
@@ -3360,7 +3364,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         event = self.get_success(self.store.get_event(event_id))
         self.assertEqual(event.sender, self.other_user)
 
-    def test_devices(self):
+    def test_devices(self) -> None:
         """Tests that logging in as a user doesn't create a new device for them."""
         # Login in as the user
         self._get_token()
@@ -3374,7 +3378,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         # We should only see the one device (from the login in `prepare`)
         self.assertEqual(len(channel.json_body["devices"]), 1)
 
-    def test_logout(self):
+    def test_logout(self) -> None:
         """Test that calling `/logout` with the token works."""
         # Login in as the user
         puppet_token = self._get_token()
@@ -3397,7 +3401,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         )
         self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
 
-    def test_user_logout_all(self):
+    def test_user_logout_all(self) -> None:
         """Tests that the target user calling `/logout/all` does *not* expire
         the token.
         """
@@ -3424,7 +3428,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         )
         self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
 
-    def test_admin_logout_all(self):
+    def test_admin_logout_all(self) -> None:
         """Tests that the admin user calling `/logout/all` does expire the
         token.
         """
@@ -3464,7 +3468,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
             "form_secret": "123secret",
         }
     )
-    def test_consent(self):
+    def test_consent(self) -> None:
         """Test that sending a message is not subject to the privacy policies."""
         # Have the admin user accept the terms.
         self.get_success(self.store.user_set_consent_version(self.admin_user, "1.0"))
@@ -3492,7 +3496,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
     @override_config(
         {"limit_usage_by_mau": True, "max_mau_value": 1, "mau_trial_days": 0}
     )
-    def test_mau_limit(self):
+    def test_mau_limit(self) -> None:
         # Create a room as the admin user. This will bump the monthly active users to 1.
         room_id = self.helper.create_room_as(self.admin_user, tok=self.admin_user_tok)
 
@@ -3524,14 +3528,14 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
         login.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.admin_user = self.register_user("admin", "pass", admin=True)
         self.admin_user_tok = self.login("admin", "pass")
 
         self.other_user = self.register_user("user", "pass")
-        self.url = self.url_prefix % self.other_user
+        self.url = self.url_prefix % self.other_user  # type: ignore[attr-defined]
 
-    def test_no_auth(self):
+    def test_no_auth(self) -> None:
         """
         Try to get information of an user without authentication.
         """
@@ -3539,7 +3543,7 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
-    def test_requester_is_not_admin(self):
+    def test_requester_is_not_admin(self) -> None:
         """
         If the user is not a server admin, an error is returned.
         """
@@ -3554,11 +3558,11 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
-    def test_user_is_not_local(self):
+    def test_user_is_not_local(self) -> None:
         """
         Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
         """
-        url = self.url_prefix % "@unknown_person:unknown_domain"
+        url = self.url_prefix % "@unknown_person:unknown_domain"  # type: ignore[attr-defined]
 
         channel = self.make_request(
             "GET",
@@ -3568,7 +3572,7 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual("Can only whois a local user", channel.json_body["error"])
 
-    def test_get_whois_admin(self):
+    def test_get_whois_admin(self) -> None:
         """
         The lookup should succeed for an admin.
         """
@@ -3581,7 +3585,7 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(self.other_user, channel.json_body["user_id"])
         self.assertIn("devices", channel.json_body)
 
-    def test_get_whois_user(self):
+    def test_get_whois_user(self) -> None:
         """
         The lookup should succeed for a normal user looking up their own information.
         """
@@ -3604,7 +3608,7 @@ class ShadowBanRestTestCase(unittest.HomeserverTestCase):
         login.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = hs.get_datastore()
 
         self.admin_user = self.register_user("admin", "pass", admin=True)
@@ -3617,7 +3621,7 @@ class ShadowBanRestTestCase(unittest.HomeserverTestCase):
         )
 
     @parameterized.expand(["POST", "DELETE"])
-    def test_no_auth(self, method: str):
+    def test_no_auth(self, method: str) -> None:
         """
         Try to get information of an user without authentication.
         """
@@ -3626,7 +3630,7 @@ class ShadowBanRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     @parameterized.expand(["POST", "DELETE"])
-    def test_requester_is_not_admin(self, method: str):
+    def test_requester_is_not_admin(self, method: str) -> None:
         """
         If the user is not a server admin, an error is returned.
         """
@@ -3637,7 +3641,7 @@ class ShadowBanRestTestCase(unittest.HomeserverTestCase):
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     @parameterized.expand(["POST", "DELETE"])
-    def test_user_is_not_local(self, method: str):
+    def test_user_is_not_local(self, method: str) -> None:
         """
         Tests that shadow-banning for a user that is not a local returns a HTTPStatus.BAD_REQUEST
         """
@@ -3646,7 +3650,7 @@ class ShadowBanRestTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(method, url, access_token=self.admin_user_tok)
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
 
-    def test_success(self):
+    def test_success(self) -> None:
         """
         Shadow-banning should succeed for an admin.
         """
@@ -3682,7 +3686,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
         login.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = hs.get_datastore()
 
         self.admin_user = self.register_user("admin", "pass", admin=True)
@@ -3695,7 +3699,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
         )
 
     @parameterized.expand(["GET", "POST", "DELETE"])
-    def test_no_auth(self, method: str):
+    def test_no_auth(self, method: str) -> None:
         """
         Try to get information of a user without authentication.
         """
@@ -3705,7 +3709,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "POST", "DELETE"])
-    def test_requester_is_no_admin(self, method: str):
+    def test_requester_is_no_admin(self, method: str) -> None:
         """
         If the user is not a server admin, an error is returned.
         """
@@ -3721,7 +3725,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "POST", "DELETE"])
-    def test_user_does_not_exist(self, method: str):
+    def test_user_does_not_exist(self, method: str) -> None:
         """
         Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
         """
@@ -3743,7 +3747,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             ("DELETE", "Only local users can be ratelimited"),
         ]
     )
-    def test_user_is_not_local(self, method: str, error_msg: str):
+    def test_user_is_not_local(self, method: str, error_msg: str) -> None:
         """
         Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
         """
@@ -3760,7 +3764,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual(error_msg, channel.json_body["error"])
 
-    def test_invalid_parameter(self):
+    def test_invalid_parameter(self) -> None:
         """
         If parameters are invalid, an error is returned.
         """
@@ -3808,7 +3812,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
         self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
-    def test_return_zero_when_null(self):
+    def test_return_zero_when_null(self) -> None:
         """
         If values in database are `null` API should return an int `0`
         """
@@ -3834,7 +3838,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
         self.assertEqual(0, channel.json_body["messages_per_second"])
         self.assertEqual(0, channel.json_body["burst_count"])
 
-    def test_success(self):
+    def test_success(self) -> None:
         """
         Rate-limiting (set/update/delete) should succeed for an admin.
         """
@@ -3908,7 +3912,7 @@ class AccountDataTestCase(unittest.HomeserverTestCase):
         login.register_servlets,
     ]
 
-    def prepare(self, reactor, clock, hs) -> None:
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = hs.get_datastore()
 
         self.admin_user = self.register_user("admin", "pass", admin=True)
diff --git a/tests/rest/admin/test_username_available.py b/tests/rest/admin/test_username_available.py
index 7978626e7..b21f6d468 100644
--- a/tests/rest/admin/test_username_available.py
+++ b/tests/rest/admin/test_username_available.py
@@ -14,9 +14,13 @@
 
 from http import HTTPStatus
 
+from twisted.test.proto_helpers import MemoryReactor
+
 import synapse.rest.admin
 from synapse.api.errors import Codes, SynapseError
 from synapse.rest.client import login
+from synapse.server import HomeServer
+from synapse.util import Clock
 
 from tests import unittest
 
@@ -28,11 +32,11 @@ class UsernameAvailableTestCase(unittest.HomeserverTestCase):
     ]
     url = "/_synapse/admin/v1/username_available"
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.register_user("admin", "pass", admin=True)
         self.admin_user_tok = self.login("admin", "pass")
 
-        async def check_username(username):
+        async def check_username(username: str) -> bool:
             if username == "allowed":
                 return True
             raise SynapseError(
@@ -44,24 +48,24 @@ class UsernameAvailableTestCase(unittest.HomeserverTestCase):
         handler = self.hs.get_registration_handler()
         handler.check_username = check_username
 
-    def test_username_available(self):
+    def test_username_available(self) -> None:
         """
         The endpoint should return a HTTPStatus.OK response if the username does not exist
         """
 
         url = "%s?username=%s" % (self.url, "allowed")
-        channel = self.make_request("GET", url, None, self.admin_user_tok)
+        channel = self.make_request("GET", url, access_token=self.admin_user_tok)
 
         self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
         self.assertTrue(channel.json_body["available"])
 
-    def test_username_unavailable(self):
+    def test_username_unavailable(self) -> None:
         """
         The endpoint should return a HTTPStatus.OK response if the username does not exist
         """
 
         url = "%s?username=%s" % (self.url, "disallowed")
-        channel = self.make_request("GET", url, None, self.admin_user_tok)
+        channel = self.make_request("GET", url, access_token=self.admin_user_tok)
 
         self.assertEqual(
             HTTPStatus.BAD_REQUEST,