diff --git a/nova/tests/functional/api_sample_tests/api_sample_base.py b/nova/tests/functional/api_sample_tests/api_sample_base.py
index d9ac77f1ae..4325ba4c52 100644
--- a/nova/tests/functional/api_sample_tests/api_sample_base.py
+++ b/nova/tests/functional/api_sample_tests/api_sample_base.py
@@ -53,7 +53,7 @@ CONF = nova.conf.CONF
 
 
 class ApiSampleTestBaseV21(testscenarios.WithScenarios,
-                          api_samples_test_base.ApiSampleTestBase):
+                           api_samples_test_base.ApiSampleTestBase):
     SUPPORTS_CELLS = False
 
     api_major_version = 'v2'
diff --git a/nova/tests/functional/api_sample_tests/test_instance_actions.py b/nova/tests/functional/api_sample_tests/test_instance_actions.py
index 785575fde8..cd82528d61 100644
--- a/nova/tests/functional/api_sample_tests/test_instance_actions.py
+++ b/nova/tests/functional/api_sample_tests/test_instance_actions.py
@@ -15,11 +15,10 @@
 
 from nova.tests.functional.api_sample_tests import test_servers
 from nova.tests.functional import api_samples_test_base
-from nova.tests.functional import integrated_helpers
 
 
-class ServerActionsSampleJsonTest(test_servers.ServersSampleBase,
-                                  integrated_helpers.InstanceHelperMixin):
+class ServerActionsSampleJsonTest(test_servers.ServersSampleBase):
+
     microversion = None
     ADMIN_API = True
     sample_dir = 'os-instance-actions'
diff --git a/nova/tests/functional/api_sample_tests/test_multinic.py b/nova/tests/functional/api_sample_tests/test_multinic.py
index 526e4dc6b5..c66f1d5c1f 100644
--- a/nova/tests/functional/api_sample_tests/test_multinic.py
+++ b/nova/tests/functional/api_sample_tests/test_multinic.py
@@ -15,11 +15,9 @@
 
 from nova.tests import fixtures
 from nova.tests.functional.api_sample_tests import api_sample_base
-from nova.tests.functional import integrated_helpers
 
 
-class MultinicSampleJsonTest(integrated_helpers.InstanceHelperMixin,
-                             api_sample_base.ApiSampleTestBaseV21):
+class MultinicSampleJsonTest(api_sample_base.ApiSampleTestBaseV21):
     ADMIN_API = True
     sample_dir = "os-multinic"
 
diff --git a/nova/tests/functional/compute/test_live_migration.py b/nova/tests/functional/compute/test_live_migration.py
index 1966b3d13d..083dadf774 100644
--- a/nova/tests/functional/compute/test_live_migration.py
+++ b/nova/tests/functional/compute/test_live_migration.py
@@ -38,8 +38,7 @@ class FakeCinderError(object):
             raise exception.CinderConnectionFailed(reason='Fake Cinder error')
 
 
-class LiveMigrationCinderFailure(integrated_helpers._IntegratedTestBase,
-                                 integrated_helpers.InstanceHelperMixin):
+class LiveMigrationCinderFailure(integrated_helpers._IntegratedTestBase):
     api_major_version = 'v2.1'
     microversion = 'latest'
 
@@ -47,7 +46,7 @@ class LiveMigrationCinderFailure(integrated_helpers._IntegratedTestBase,
         super(LiveMigrationCinderFailure, self).setUp()
         fake_notifier.stub_notifier(self)
         self.addCleanup(fake_notifier.reset)
-        # Start a second compte node (the first one was started for us by
+        # Start a second compute node (the first one was started for us by
         # _IntegratedTestBase. set_nodes() is needed to avoid duplicate
         # nodenames. See comments in test_bug_1702454.py.
         self.compute2 = self.start_service('compute', host='host2')
diff --git a/nova/tests/functional/db/test_virtual_interface.py b/nova/tests/functional/db/test_virtual_interface.py
index 3ce618e1c0..9ab2dd1445 100644
--- a/nova/tests/functional/db/test_virtual_interface.py
+++ b/nova/tests/functional/db/test_virtual_interface.py
@@ -55,8 +55,7 @@ def _verify_list_fulfillment(context, instance_uuid):
 
 
 class VirtualInterfaceListMigrationTestCase(
-        integrated_helpers._IntegratedTestBase,
-        integrated_helpers.InstanceHelperMixin):
+        integrated_helpers._IntegratedTestBase):
 
     ADMIN_API = True
     api_major_version = 'v2.1'
diff --git a/nova/tests/functional/integrated_helpers.py b/nova/tests/functional/integrated_helpers.py
index 7b01d547dd..57eca61606 100644
--- a/nova/tests/functional/integrated_helpers.py
+++ b/nova/tests/functional/integrated_helpers.py
@@ -242,7 +242,7 @@ class InstanceHelperMixin(object):
         return api.post_aggregate(body)['id']
 
 
-class _IntegratedTestBase(test.TestCase):
+class _IntegratedTestBase(test.TestCase, InstanceHelperMixin):
     REQUIRES_LOCKING = True
     ADMIN_API = False
     # This indicates whether to include the project ID in the URL for API
@@ -320,37 +320,6 @@ class _IntegratedTestBase(test.TestCase):
         return (generate_new_element(flavor_names, 'flavor'),
                 int(generate_new_element(flavor_ids, '', True)))
 
-    def _build_minimal_create_server_request(self, name=None, image_uuid=None,
-                                             flavor_id=None, networks=None,
-                                             az=None, host=None):
-        server = {}
-
-        if not image_uuid:
-            # NOTE(takashin): In API version 2.36, image APIs were deprecated.
-            # In API version 2.36 or greater, self.api.get_images() returns
-            # a 404 error. In that case, 'image_uuid' should be specified.
-            image_uuid = self.api.get_images()[0]['id']
-        server['imageRef'] = image_uuid
-
-        if not name:
-            name = ''.join(
-                random.choice(string.ascii_lowercase) for i in range(10))
-        server['name'] = name
-
-        if not flavor_id:
-            # Set a valid flavorId
-            flavor_id = self.api.get_flavors()[0]['id']
-        server['flavorRef'] = 'http://fake.server/%s' % flavor_id
-
-        if networks is not None:
-            server['networks'] = networks
-        if az is not None:
-            server['availability_zone'] = az
-        # This requires at least microversion 2.74 to work
-        if host is not None:
-            server['host'] = host
-        return server
-
     def _create_flavor_body(self, name, ram, vcpus, disk, ephemeral, id, swap,
                             rxtx_factor, is_public):
         return {
diff --git a/nova/tests/functional/regressions/test_bug_1404867.py b/nova/tests/functional/regressions/test_bug_1404867.py
index fa15dc9006..4581e1f0e4 100644
--- a/nova/tests/functional/regressions/test_bug_1404867.py
+++ b/nova/tests/functional/regressions/test_bug_1404867.py
@@ -16,8 +16,7 @@ from nova.tests import fixtures as nova_fixtures
 from nova.tests.functional import integrated_helpers
 
 
-class DeleteWithReservedVolumes(integrated_helpers._IntegratedTestBase,
-                                integrated_helpers.InstanceHelperMixin):
+class DeleteWithReservedVolumes(integrated_helpers._IntegratedTestBase):
     """Test deleting of an instance in error state that has a reserved volume.
 
     This test boots a server from volume which will fail to be scheduled,
diff --git a/nova/tests/functional/regressions/test_bug_1669054.py b/nova/tests/functional/regressions/test_bug_1669054.py
index 1054ae9dbd..99e1d728f1 100644
--- a/nova/tests/functional/regressions/test_bug_1669054.py
+++ b/nova/tests/functional/regressions/test_bug_1669054.py
@@ -15,8 +15,7 @@ from nova import objects
 from nova.tests.functional import integrated_helpers
 
 
-class ResizeEvacuateTestCase(integrated_helpers._IntegratedTestBase,
-                             integrated_helpers.InstanceHelperMixin):
+class ResizeEvacuateTestCase(integrated_helpers._IntegratedTestBase):
     """Regression test for bug 1669054 introduced in Newton.
 
     When resizing a server, if CONF.allow_resize_to_same_host is False,
diff --git a/nova/tests/functional/regressions/test_bug_1732947.py b/nova/tests/functional/regressions/test_bug_1732947.py
index 97f207f442..a373c62c4c 100644
--- a/nova/tests/functional/regressions/test_bug_1732947.py
+++ b/nova/tests/functional/regressions/test_bug_1732947.py
@@ -19,8 +19,7 @@ from nova.tests.functional import integrated_helpers
 CONF = nova.conf.CONF
 
 
-class RebuildVolumeBackedSameImage(integrated_helpers._IntegratedTestBase,
-                                   integrated_helpers.InstanceHelperMixin):
+class RebuildVolumeBackedSameImage(integrated_helpers._IntegratedTestBase):
     """Tests the regression in bug 1732947 where rebuilding a volume-backed
     instance with the original image still results in conductor calling the
     scheduler to validate the image. This is because the instance.image_ref
diff --git a/nova/tests/functional/regressions/test_bug_1823370.py b/nova/tests/functional/regressions/test_bug_1823370.py
index 9edf756bc9..6e8c912165 100644
--- a/nova/tests/functional/regressions/test_bug_1823370.py
+++ b/nova/tests/functional/regressions/test_bug_1823370.py
@@ -14,8 +14,7 @@ from nova.tests import fixtures as nova_fixtures
 from nova.tests.functional import integrated_helpers
 
 
-class MultiCellEvacuateTestCase(integrated_helpers._IntegratedTestBase,
-                                integrated_helpers.InstanceHelperMixin):
+class MultiCellEvacuateTestCase(integrated_helpers._IntegratedTestBase):
     """Recreate test for bug 1823370 which was introduced in Pike.
 
     When evacuating a server, the request to the scheduler should be restricted
diff --git a/nova/tests/functional/test_aggregates.py b/nova/tests/functional/test_aggregates.py
index b0d277012a..be314cfea5 100644
--- a/nova/tests/functional/test_aggregates.py
+++ b/nova/tests/functional/test_aggregates.py
@@ -838,7 +838,7 @@ class TestAggregateFiltersTogether(AggregateRequestFiltersTest):
 
 
 class TestAggregateMultiTenancyIsolationFilter(
-    test.TestCase, integrated_helpers.InstanceHelperMixin):
+        test.TestCase, integrated_helpers.InstanceHelperMixin):
 
     def _start_compute(self, host):
         self.start_service('compute', host=host)
diff --git a/nova/tests/functional/test_boot_from_volume.py b/nova/tests/functional/test_boot_from_volume.py
index 3bed083181..d6b9220c63 100644
--- a/nova/tests/functional/test_boot_from_volume.py
+++ b/nova/tests/functional/test_boot_from_volume.py
@@ -25,8 +25,7 @@ from nova.tests.unit.image import fake as fake_image
 from nova.tests.unit import policy_fixture
 
 
-class BootFromVolumeTest(integrated_helpers.InstanceHelperMixin,
-                         test_servers.ServersTestBase):
+class BootFromVolumeTest(test_servers.ServersTestBase):
 
     def _get_hypervisor_stats(self):
         response = self.admin_api.api_get('/os-hypervisors/statistics')
@@ -118,8 +117,7 @@ class BootFromVolumeTest(integrated_helpers.InstanceHelperMixin,
         # Shelve
         post_data = {'shelve': None}
         self.api.post_server_action(server_id, post_data)
-        self._wait_for_state_change(created_server,
-                                    'SHELVED_OFFLOADED')
+        self._wait_for_state_change(created_server, 'SHELVED_OFFLOADED')
 
         # Check that hypervisor local disk reporting is still 0
         self._verify_zero_local_gb_used()
diff --git a/nova/tests/functional/test_conf_max_attach_disk_devices.py b/nova/tests/functional/test_conf_max_attach_disk_devices.py
index a6dcb0c228..538c008c0f 100644
--- a/nova/tests/functional/test_conf_max_attach_disk_devices.py
+++ b/nova/tests/functional/test_conf_max_attach_disk_devices.py
@@ -16,12 +16,10 @@ import six
 
 from nova.tests import fixtures as nova_fixtures
 from nova.tests.functional.api import client
-from nova.tests.functional import integrated_helpers
 from nova.tests.functional import test_servers
 
 
-class ConfigurableMaxDiskDevicesTest(integrated_helpers.InstanceHelperMixin,
-                                     test_servers.ServersTestBase):
+class ConfigurableMaxDiskDevicesTest(test_servers.ServersTestBase):
     def setUp(self):
         super(ConfigurableMaxDiskDevicesTest, self).setUp()
         self.cinder = self.useFixture(
diff --git a/nova/tests/functional/test_multiattach.py b/nova/tests/functional/test_multiattach.py
index 42193c2f23..589677a2ae 100644
--- a/nova/tests/functional/test_multiattach.py
+++ b/nova/tests/functional/test_multiattach.py
@@ -15,8 +15,7 @@ from nova.tests import fixtures as nova_fixtures
 from nova.tests.functional import integrated_helpers
 
 
-class TestMultiattachVolumes(integrated_helpers._IntegratedTestBase,
-                             integrated_helpers.InstanceHelperMixin):
+class TestMultiattachVolumes(integrated_helpers._IntegratedTestBase):
     """Functional tests for creating a server from a multiattach volume
     and attaching a multiattach volume to a server.
 
diff --git a/nova/tests/functional/test_nova_manage.py b/nova/tests/functional/test_nova_manage.py
index 43beae0baf..0bc9ef938f 100644
--- a/nova/tests/functional/test_nova_manage.py
+++ b/nova/tests/functional/test_nova_manage.py
@@ -1430,9 +1430,7 @@ class TestDBArchiveDeletedRows(integrated_helpers._IntegratedTestBase):
         # Now delete one server and then we can archive.
         server = self.api.get_server(server['id'])
         self.api.delete_server(server['id'])
-        helper = integrated_helpers.InstanceHelperMixin()
-        helper.api = self.api
-        helper._wait_until_deleted(server)
+        self._wait_until_deleted(server)
         # Now archive.
         self.cli.archive_deleted_rows(verbose=True)
         # Assert only one instance_group_member record was deleted.
diff --git a/nova/tests/functional/test_servers.py b/nova/tests/functional/test_servers.py
index 8c4dd6ebdb..0a60b54ab2 100644
--- a/nova/tests/functional/test_servers.py
+++ b/nova/tests/functional/test_servers.py
@@ -75,43 +75,6 @@ class ServersTestBase(integrated_helpers._IntegratedTestBase):
         self.computes = {}
         super(ServersTestBase, self).setUp()
 
-    def _wait_for_server_parameter(self, server, expected_params,
-                                   max_retries=10):
-        api = getattr(self, 'admin_api', self.api)
-        retry_count = 0
-        while True:
-            server = api.get_server(server['id'])
-            if all([server[attr] == expected_params[attr]
-                    for attr in expected_params]):
-                break
-            retry_count += 1
-            if retry_count == max_retries:
-                self.fail('Wait for state change failed, '
-                          'expected_params=%s, server=%s' % (
-                              expected_params, server))
-            time.sleep(0.5)
-
-        return server
-
-    def _wait_for_state_change(self, server, expected_status, max_retries=10):
-        return self._wait_for_server_parameter(
-            server, {'status': expected_status}, max_retries)
-
-    # TODO(stephenfin): Remove this once we subclass 'InstanceHelperMixin'
-    def _wait_until_deleted(self, server):
-        initially_in_error = server.get('status') == 'ERROR'
-        try:
-            for i in range(40):
-                server = self.api.get_server(server['id'])
-                if not initially_in_error and server['status'] == 'ERROR':
-                    self.fail('Server went to error state instead of'
-                              'disappearing.')
-                time.sleep(0.5)
-
-            self.fail('Server failed to delete.')
-        except client.OpenStackApiNotFoundException:
-            return
-
     def _delete_server(self, server):
         # Delete the server
         self.api.delete_server(server['id'])
@@ -1366,8 +1329,7 @@ class ServerTestV269(ServersTestBase):
                 self.assertIn('image', server)
 
 
-class ServerRebuildTestCase(integrated_helpers._IntegratedTestBase,
-                            integrated_helpers.InstanceHelperMixin):
+class ServerRebuildTestCase(integrated_helpers._IntegratedTestBase):
     api_major_version = 'v2.1'
     # We have to cap the microversion at 2.38 because that's the max we
     # can use to update image metadata via our compute images proxy API.