diff --git a/uncloud/uncloud/models.py b/uncloud/uncloud/models.py
new file mode 100644
index 0000000..7ca5dfa
--- /dev/null
+++ b/uncloud/uncloud/models.py
@@ -0,0 +1,22 @@
+from django.db import models
+from django.contrib.postgres.fields import JSONField
+
+class UncloudModel(models.Model):
+    """
+    This class extends the standard model with an
+    extra_data field that can be used to include public,
+    but internal information.
+
+    For instance if you migrate from an existing virtualisation
+    framework to uncloud.
+
+    The extra_data attribute should be considered a hack and whenever
+    data is necessary for running uncloud, it should **not** be stored
+    in there.
+
+    """
+
+    extra_data = JSONField(editable=False, blank=True, null=True)
+
+    class Meta:
+        abstract = True
diff --git a/uncloud/uncloud_pay/models.py b/uncloud/uncloud_pay/models.py
index a11c3c1..532e130 100644
--- a/uncloud/uncloud_pay/models.py
+++ b/uncloud/uncloud_pay/models.py
@@ -19,8 +19,7 @@ from decimal import Decimal
 import uncloud_pay.stripe
 from uncloud_pay.helpers import beginning_of_month, end_of_month
 from uncloud import AMOUNT_DECIMALS, AMOUNT_MAX_DIGITS
-
-
+from uncloud.models import UncloudModel
 
 
 # Used to generate bill due dates.
@@ -418,6 +417,7 @@ class OrderRecord(models.Model):
 
     description = models.TextField()
 
+
     @property
     def recurring_period(self):
         return self.order.recurring_period
@@ -436,7 +436,7 @@ class OrderRecord(models.Model):
 
 # Abstract (= no database representation) class used as parent for products
 # (e.g.  uncloud_vm.models.VMProduct).
-class Product(models.Model):
+class Product(UncloudModel):
     uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
     owner = models.ForeignKey(get_user_model(),
                               on_delete=models.CASCADE,
diff --git a/uncloud/uncloud_vm/migrations/0005_auto_20200321_1058.py b/uncloud/uncloud_vm/migrations/0005_auto_20200321_1058.py
new file mode 100644
index 0000000..3799e6a
--- /dev/null
+++ b/uncloud/uncloud_vm/migrations/0005_auto_20200321_1058.py
@@ -0,0 +1,50 @@
+# Generated by Django 3.0.3 on 2020-03-21 10:58
+
+import django.contrib.postgres.fields.jsonb
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('uncloud_vm', '0004_remove_vmproduct_vmid'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='vmdiskimageproduct',
+            name='extra_data',
+            field=django.contrib.postgres.fields.jsonb.JSONField(blank=True, editable=False, null=True),
+        ),
+        migrations.AddField(
+            model_name='vmdiskproduct',
+            name='extra_data',
+            field=django.contrib.postgres.fields.jsonb.JSONField(blank=True, editable=False, null=True),
+        ),
+        migrations.AddField(
+            model_name='vmhost',
+            name='extra_data',
+            field=django.contrib.postgres.fields.jsonb.JSONField(blank=True, editable=False, null=True),
+        ),
+        migrations.AddField(
+            model_name='vmproduct',
+            name='extra_data',
+            field=django.contrib.postgres.fields.jsonb.JSONField(blank=True, editable=False, null=True),
+        ),
+        migrations.AddField(
+            model_name='vmsnapshotproduct',
+            name='extra_data',
+            field=django.contrib.postgres.fields.jsonb.JSONField(blank=True, editable=False, null=True),
+        ),
+        migrations.AlterField(
+            model_name='vmdiskproduct',
+            name='vm',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='disks', to='uncloud_vm.VMProduct'),
+        ),
+        migrations.AlterField(
+            model_name='vmsnapshotproduct',
+            name='vm',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='snapshots', to='uncloud_vm.VMProduct'),
+        ),
+    ]
diff --git a/uncloud/uncloud_vm/models.py b/uncloud/uncloud_vm/models.py
index 7e38ded..bdd3a43 100644
--- a/uncloud/uncloud_vm/models.py
+++ b/uncloud/uncloud_vm/models.py
@@ -3,10 +3,13 @@ import uuid
 from django.db import models
 from django.contrib.auth import get_user_model
 
+
 # Uncomment if you override model's clean method
 # from django.core.exceptions import ValidationError
 
 from uncloud_pay.models import Product, RecurringPeriod
+from uncloud.models import UncloudModel
+
 import uncloud_pay.models as pay_models
 import uncloud_storage.models
 
@@ -22,7 +25,7 @@ STATUS_CHOICES = (
 STATUS_DEFAULT = 'pending'
 
 
-class VMHost(models.Model):
+class VMHost(UncloudModel):
     uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
 
     # 253 is the maximum DNS name length
@@ -99,7 +102,7 @@ class VMWithOSProduct(VMProduct):
     pass
 
 
-class VMDiskImageProduct(models.Model):
+class VMDiskImageProduct(UncloudModel):
     """
     Images are used for cloning/linking.
 
@@ -138,7 +141,7 @@ class VMDiskImageProduct(models.Model):
 
 
 
-class VMDiskProduct(models.Model):
+class VMDiskProduct(UncloudModel):
     """
     The VMDiskProduct is attached to a VM.
 
diff --git a/uncloud/ungleich_service/migrations/0002_matrixserviceproduct_extra_data.py b/uncloud/ungleich_service/migrations/0002_matrixserviceproduct_extra_data.py
new file mode 100644
index 0000000..f755ddb
--- /dev/null
+++ b/uncloud/ungleich_service/migrations/0002_matrixserviceproduct_extra_data.py
@@ -0,0 +1,19 @@
+# Generated by Django 3.0.3 on 2020-03-21 10:58
+
+import django.contrib.postgres.fields.jsonb
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('ungleich_service', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='matrixserviceproduct',
+            name='extra_data',
+            field=django.contrib.postgres.fields.jsonb.JSONField(blank=True, editable=False, null=True),
+        ),
+    ]