diff --git a/src/core/devices/nm-device.c b/src/core/devices/nm-device.c
index 3161560ee9..b8a53bff0a 100644
--- a/src/core/devices/nm-device.c
+++ b/src/core/devices/nm-device.c
@@ -12968,7 +12968,7 @@ impl_device_get_applied_connection(NMDBusObject *                     obj,
     var_settings =
         nm_connection_to_dbus(applied_connection, NM_CONNECTION_SERIALIZE_WITH_NON_SECRET);
     if (!var_settings)
-        var_settings = g_variant_new_array(G_VARIANT_TYPE("{sa{sv}}"), NULL, 0);
+        var_settings = nm_g_variant_singleton_aLsaLsvII();
 
     g_dbus_method_invocation_return_value(
         invocation,
@@ -17900,7 +17900,6 @@ get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
 {
     NMDevice *       self = NM_DEVICE(object);
     NMDevicePrivate *priv = NM_DEVICE_GET_PRIVATE(self);
-    GVariantBuilder  array_builder;
 
     switch (prop_id) {
     case PROP_UDI:
@@ -18051,12 +18050,10 @@ get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
         g_value_set_uint(value, priv->metered);
         break;
     case PROP_LLDP_NEIGHBORS:
-        if (priv->lldp_listener)
-            g_value_set_variant(value, nm_lldp_listener_get_neighbors(priv->lldp_listener));
-        else {
-            g_variant_builder_init(&array_builder, G_VARIANT_TYPE("aa{sv}"));
-            g_value_take_variant(value, g_variant_builder_end(&array_builder));
-        }
+        g_value_set_variant(value,
+                            priv->lldp_listener
+                                ? nm_lldp_listener_get_neighbors(priv->lldp_listener)
+                                : nm_g_variant_singleton_aaLsvI());
         break;
     case PROP_REAL:
         g_value_set_boolean(value, nm_device_is_real(self));
diff --git a/src/core/nm-dhcp-config.c b/src/core/nm-dhcp-config.c
index 718d3c90ec..c26b371dca 100644
--- a/src/core/nm-dhcp-config.c
+++ b/src/core/nm-dhcp-config.c
@@ -116,8 +116,7 @@ get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
 
     switch (prop_id) {
     case PROP_OPTIONS:
-        g_value_set_variant(value,
-                            priv->options ?: g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0));
+        g_value_set_variant(value, priv->options ?: nm_g_variant_singleton_aLsvI());
         break;
     default:
         G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
diff --git a/src/core/nm-dispatcher.c b/src/core/nm-dispatcher.c
index 5862dd0a82..81076810e4 100644
--- a/src/core/nm-dispatcher.c
+++ b/src/core/nm-dispatcher.c
@@ -552,7 +552,7 @@ _dispatcher_call(NMDispatcherAction    action,
         connection_dict =
             nm_connection_to_dbus(applied_connection, NM_CONNECTION_SERIALIZE_WITH_NON_SECRET);
     else
-        connection_dict = g_variant_new_array(G_VARIANT_TYPE("{sa{sv}}"), NULL, 0);
+        connection_dict = nm_g_variant_singleton_aLsaLsvII();
 
     g_variant_builder_init(&connection_props, G_VARIANT_TYPE_VARDICT);
     if (settings_connection) {
@@ -620,8 +620,8 @@ _dispatcher_call(NMDispatcherAction    action,
                       &device_proxy_props,
                       &device_ip4_props,
                       &device_ip6_props,
-                      device_dhcp4_props ?: g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0),
-                      device_dhcp6_props ?: g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0),
+                      device_dhcp4_props ?: nm_g_variant_singleton_aLsvI(),
+                      device_dhcp6_props ?: nm_g_variant_singleton_aLsvI(),
                       connectivity_state_string,
                       vpn_iface ?: "",
                       &vpn_proxy_props,
diff --git a/src/core/nm-manager.c b/src/core/nm-manager.c
index b3e6535506..50d2e3225a 100644
--- a/src/core/nm-manager.c
+++ b/src/core/nm-manager.c
@@ -5637,7 +5637,7 @@ activation_add_done(NMSettings *           settings,
         result_floating = g_variant_new("(oo@a{sv})",
                                         nm_dbus_object_get_path(NM_DBUS_OBJECT(new_connection)),
                                         nm_dbus_object_get_path(NM_DBUS_OBJECT(active)),
-                                        g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0));
+                                        nm_g_variant_singleton_aLsvI());
     }
     g_dbus_method_invocation_return_value(context, result_floating);
 
diff --git a/src/core/settings/nm-settings-connection.c b/src/core/settings/nm-settings-connection.c
index 294cb04705..7b5477f477 100644
--- a/src/core/settings/nm-settings-connection.c
+++ b/src/core/settings/nm-settings-connection.c
@@ -1868,7 +1868,7 @@ dbus_get_agent_secrets_cb(NMSettingsConnection *      self,
         dict = nm_connection_to_dbus(nm_settings_connection_get_connection(self),
                                      NM_CONNECTION_SERIALIZE_WITH_SECRETS);
         if (!dict)
-            dict = g_variant_new_array(G_VARIANT_TYPE("{sa{sv}}"), NULL, 0);
+            dict = nm_g_variant_singleton_aLsaLsvII();
         g_dbus_method_invocation_return_value(context, g_variant_new("(@a{sa{sv}})", dict));
     }
 }
diff --git a/src/libnm-client-impl/nm-client.c b/src/libnm-client-impl/nm-client.c
index f4a93f9f3c..4dd9bccb60 100644
--- a/src/libnm-client-impl/nm-client.c
+++ b/src/libnm-client-impl/nm-client.c
@@ -5137,11 +5137,11 @@ _add_and_activate_connection(NMClient *          self,
     if (partial)
         arg_connection = nm_connection_to_dbus(partial, NM_CONNECTION_SERIALIZE_ALL);
     if (!arg_connection)
-        arg_connection = g_variant_new_array(G_VARIANT_TYPE("{sa{sv}}"), NULL, 0);
+        arg_connection = nm_g_variant_singleton_aLsaLsvII();
 
     if (is_v2) {
         if (!options)
-            options = g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0);
+            options = nm_g_variant_singleton_aLsvI();
         use_add_and_activate_v2 = TRUE;
         source_tag              = nm_client_add_and_activate_connection2;
     } else {
@@ -5641,7 +5641,7 @@ _add_connection_call(NMClient *                    self,
     NML_NMCLIENT_LOG_D(self, "AddConnection() started...");
 
     if (!settings)
-        settings = g_variant_new_array(G_VARIANT_TYPE("{sa{sv}}"), NULL, 0);
+        settings = nm_g_variant_singleton_aLsaLsvII();
 
     /* Although AddConnection2() being capable to handle also AddConnection() and
      * AddConnectionUnsaved() variants, we prefer to use the old D-Bus methods when
@@ -5678,24 +5678,23 @@ _add_connection_call(NMClient *                    self,
                              NM_DBUS_DEFAULT_TIMEOUT_MSEC,
                              _add_connection_cb_without_extra_result);
     } else {
-        _nm_client_dbus_call(
-            self,
-            self,
-            source_tag,
-            cancellable,
-            callback,
-            user_data,
-            NM_DBUS_PATH_SETTINGS,
-            NM_DBUS_INTERFACE_SETTINGS,
-            "AddConnection2",
-            g_variant_new("(@a{sa{sv}}u@a{sv})",
-                          settings,
-                          (guint32) flags,
-                          args ?: g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0)),
-            G_VARIANT_TYPE("(oa{sv})"),
-            G_DBUS_CALL_FLAGS_NONE,
-            NM_DBUS_DEFAULT_TIMEOUT_MSEC,
-            _add_connection_cb_with_extra_result);
+        _nm_client_dbus_call(self,
+                             self,
+                             source_tag,
+                             cancellable,
+                             callback,
+                             user_data,
+                             NM_DBUS_PATH_SETTINGS,
+                             NM_DBUS_INTERFACE_SETTINGS,
+                             "AddConnection2",
+                             g_variant_new("(@a{sa{sv}}u@a{sv})",
+                                           settings,
+                                           (guint32) flags,
+                                           args ?: nm_g_variant_singleton_aLsvI()),
+                             G_VARIANT_TYPE("(oa{sv})"),
+                             G_DBUS_CALL_FLAGS_NONE,
+                             NM_DBUS_DEFAULT_TIMEOUT_MSEC,
+                             _add_connection_cb_with_extra_result);
     }
 }
 
diff --git a/src/libnm-client-impl/nm-device-wifi-p2p.c b/src/libnm-client-impl/nm-device-wifi-p2p.c
index 05c430f7d3..2daaf77484 100644
--- a/src/libnm-client-impl/nm-device-wifi-p2p.c
+++ b/src/libnm-client-impl/nm-device-wifi-p2p.c
@@ -156,7 +156,7 @@ nm_device_wifi_p2p_start_find(NMDeviceWifiP2P *   device,
     g_return_if_fail(!cancellable || G_IS_CANCELLABLE(cancellable));
 
     if (!options)
-        options = g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0);
+        options = nm_g_variant_singleton_aLsvI();
 
     _nm_client_dbus_call(_nm_object_get_client(device),
                          device,
diff --git a/src/libnm-client-impl/nm-device-wifi.c b/src/libnm-client-impl/nm-device-wifi.c
index 84c3a069dc..fee7e8a2d8 100644
--- a/src/libnm-client-impl/nm-device-wifi.c
+++ b/src/libnm-client-impl/nm-device-wifi.c
@@ -309,7 +309,7 @@ nm_device_wifi_request_scan_options(NMDeviceWifi *device,
     g_return_val_if_fail(!error || !*error, FALSE);
 
     if (!options)
-        options = g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0);
+        options = nm_g_variant_singleton_aLsvI();
 
     return _nm_client_dbus_call_sync_void(_nm_object_get_client(device),
                                           cancellable,
@@ -382,7 +382,7 @@ nm_device_wifi_request_scan_options_async(NMDeviceWifi *      device,
     g_return_if_fail(!cancellable || G_IS_CANCELLABLE(cancellable));
 
     if (!options)
-        options = g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0);
+        options = nm_g_variant_singleton_aLsvI();
 
     _nm_client_dbus_call(_nm_object_get_client(device),
                          device,
diff --git a/src/libnm-client-impl/nm-device.c b/src/libnm-client-impl/nm-device.c
index ee0d88a0db..4d097935cb 100644
--- a/src/libnm-client-impl/nm-device.c
+++ b/src/libnm-client-impl/nm-device.c
@@ -2303,7 +2303,7 @@ nm_device_reapply(NMDevice *    device,
     if (connection)
         arg_connection = nm_connection_to_dbus(connection, NM_CONNECTION_SERIALIZE_ALL);
     if (!arg_connection)
-        arg_connection = g_variant_new_array(G_VARIANT_TYPE("{sa{sv}}"), NULL, 0);
+        arg_connection = nm_g_variant_singleton_aLsaLsvII();
 
     return _nm_client_dbus_call_sync_void(
         _nm_object_get_client(device),
@@ -2355,7 +2355,7 @@ nm_device_reapply_async(NMDevice *          device,
     if (connection)
         arg_connection = nm_connection_to_dbus(connection, NM_CONNECTION_SERIALIZE_ALL);
     if (!arg_connection)
-        arg_connection = g_variant_new_array(G_VARIANT_TYPE("{sa{sv}}"), NULL, 0);
+        arg_connection = nm_g_variant_singleton_aLsaLsvII();
 
     _nm_client_dbus_call(_nm_object_get_client(device),
                          device,
diff --git a/src/libnm-client-impl/nm-remote-connection.c b/src/libnm-client-impl/nm-remote-connection.c
index 007da3aa87..12d0da98ae 100644
--- a/src/libnm-client-impl/nm-remote-connection.c
+++ b/src/libnm-client-impl/nm-remote-connection.c
@@ -95,9 +95,9 @@ nm_remote_connection_update2(NMRemoteConnection *   connection,
     g_return_if_fail(!cancellable || G_IS_CANCELLABLE(cancellable));
 
     if (!settings)
-        settings = g_variant_new_array(G_VARIANT_TYPE("{sa{sv}}"), NULL, 0);
+        settings = nm_g_variant_singleton_aLsaLsvII();
     if (!args)
-        args = g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0);
+        args = nm_g_variant_singleton_aLsvI();
 
     _nm_client_dbus_call(_nm_object_get_client(connection),
                          connection,
@@ -185,7 +185,7 @@ nm_remote_connection_commit_changes(NMRemoteConnection *connection,
                       nm_connection_to_dbus(NM_CONNECTION(connection), NM_CONNECTION_SERIALIZE_ALL),
                       (guint32)(save_to_disk ? NM_SETTINGS_UPDATE2_FLAG_TO_DISK
                                              : NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY),
-                      g_variant_new_array(G_VARIANT_TYPE("{sv}"), NULL, 0)),
+                      nm_g_variant_singleton_aLsvI()),
         G_VARIANT_TYPE("(a{sv})"),
         G_DBUS_CALL_FLAGS_NONE,
         NM_DBUS_DEFAULT_TIMEOUT_MSEC,
diff --git a/src/libnm-core-impl/tests/test-secrets.c b/src/libnm-core-impl/tests/test-secrets.c
index 0d33df6e97..41dcc4b312 100644
--- a/src/libnm-core-impl/tests/test-secrets.c
+++ b/src/libnm-core-impl/tests/test-secrets.c
@@ -526,20 +526,25 @@ test_update_secrets_whole_connection(void)
 static void
 test_update_secrets_whole_connection_empty_hash(void)
 {
-    NMConnection *connection;
-    GVariant *    secrets;
-    GError *      error = NULL;
-    gboolean      success;
+    gs_unref_object NMConnection *connection = NULL;
+    GVariant *                    secrets;
+    GError *                      error = NULL;
+    gboolean                      success;
 
     /* Test that updating secrets with an empty connection hash returns success */
 
     connection = wifi_connection_new();
     secrets    = g_variant_new_array(G_VARIANT_TYPE("{sa{sv}}"), NULL, 0);
     success    = nm_connection_update_secrets(connection, NULL, secrets, &error);
-    g_assert_no_error(error);
-    g_assert(success == TRUE);
+    nmtst_assert_success(success, error);
     g_variant_unref(secrets);
-    g_object_unref(connection);
+
+    g_clear_object(&connection);
+
+    connection = wifi_connection_new();
+    secrets    = nm_g_variant_singleton_aLsaLsvII();
+    success    = nm_connection_update_secrets(connection, NULL, secrets, &error);
+    nmtst_assert_success(success, error);
 }
 
 static void