diff --git a/aleph_message/models/execution/instance.py b/aleph_message/models/execution/instance.py
index 8a4a44f..29a34cf 100644
--- a/aleph_message/models/execution/instance.py
+++ b/aleph_message/models/execution/instance.py
@@ -3,6 +3,7 @@
 from typing import List, Optional
 
 from pydantic import Field, model_validator
+from typing_extensions import Self
 
 from aleph_message.models.abstract import HashableModel
 
@@ -43,38 +44,37 @@ class InstanceContent(BaseExecutableContent):
     )
 
     @model_validator(mode="after")
-    def check_requirements(cls, values):
-        if values.requirements:
+    def check_requirements(self) -> Self:
+        if self.requirements:
+            if (
+                self.payment and (self.payment.is_stream or self.payment.is_credit)
+            ) and (not self.requirements.node or not self.requirements.node.node_hash):
+                raise ValueError(
+                    "Node hash assignment is needed for PAYG or Credit payments"
+                )
             # GPU filter only supported for QEmu instances with node_hash assigned
-            if values.requirements.gpu:
-                if (
-                    not values.requirements.node
-                    or not values.requirements.node.node_hash
-                ):
+            if self.requirements.gpu:
+                if not self.requirements.node or not self.requirements.node.node_hash:
                     raise ValueError("Node hash assignment is needed for GPU support")
 
                 if (
-                    values.environment
-                    and values.environment.hypervisor != HypervisorType.qemu
+                    self.environment
+                    and self.environment.hypervisor != HypervisorType.qemu
                 ):
                     raise ValueError("GPU option is only supported for QEmu hypervisor")
 
             # Terms and conditions filter only supported for PAYG/coco instances with node_hash assigned
-            if (
-                values.requirements.node
-                and values.requirements.node.terms_and_conditions
-            ):
-                if not values.requirements.node.node_hash:
+            if self.requirements.node and self.requirements.node.terms_and_conditions:
+                if not self.requirements.node.node_hash:
                     raise ValueError(
                         "Terms_and_conditions field needs a requirements.node.node_hash value"
                     )
 
                 if (
-                    not values.payment.is_stream
-                    and not values.environment.trusted_execution
-                ):
+                    not self.payment or not self.payment.is_stream
+                ) and not self.environment.trusted_execution:
                     raise ValueError(
                         "Only PAYG/coco instances can have a terms_and_conditions"
                     )
 
-        return values
+        return self
diff --git a/aleph_message/tests/test_models.py b/aleph_message/tests/test_models.py
index 7b5cdc7..4620292 100644
--- a/aleph_message/tests/test_models.py
+++ b/aleph_message/tests/test_models.py
@@ -245,6 +245,71 @@ def test_validation_on_gpu_hypervisor_options():
         )  # Ignore "Value error, ..."
 
 
+def test_validation_on_payg_payment_options():
+    """Ensure that a node_hash option is required for stream payments."""
+    path = Path(__file__).parent / "messages/instance_gpu_machine.json"
+    message_dict = json.loads(path.read_text())
+    message_dict["content"]["requirements"]["gpu"] = None
+    message = create_new_message(message_dict, factory=InstanceMessage)
+
+    assert isinstance(message, InstanceMessage)
+    assert hash(message.content)
+    assert message.content.payment
+    assert message.content.payment.type == PaymentType.superfluid
+    assert message.content.environment.hypervisor == HypervisorType.qemu
+
+    message_dict["content"]["requirements"]["node"] = None
+    try:
+        _ = create_new_message(message_dict, factory=InstanceMessage)
+        raise AssertionError("An exception should have been raised before this point.")
+    except ValidationError as e:
+        assert e.errors()[0]["loc"] in [("content",), ("content", "__root__")]
+
+        error_msg = e.errors()[0]["msg"]
+        assert (
+            "Node hash assignment is needed for PAYG or Credit payments" in error_msg
+        )  # Ignore "Value error, ..."
+
+
+def test_validation_on_credits_payment_options():
+    """Ensure that a node_hash option is required for credit payments."""
+    path = Path(__file__).parent / "messages/instance_gpu_machine.json"
+    message_dict = json.loads(path.read_text())
+    # Patch the gpu field with some info
+    message_dict["content"]["payment"]["type"] = "credit"
+    message_dict["content"]["payment"]["receiver"] = None
+    message = create_new_message(message_dict, factory=InstanceMessage)
+
+    assert isinstance(message, InstanceMessage)
+    assert hash(message.content)
+    assert message.content.payment
+    assert message.content.payment.type == PaymentType.credit
+    assert message.content.environment.hypervisor == HypervisorType.qemu
+
+    # Remove gpu field with some info
+    message_dict["content"]["requirements"]["gpu"] = None
+    message = create_new_message(message_dict, factory=InstanceMessage)
+
+    assert isinstance(message, InstanceMessage)
+    assert hash(message.content)
+    assert message.content.payment
+    assert message.content.payment.type == PaymentType.credit
+    assert message.content.environment.hypervisor == HypervisorType.qemu
+    assert message.content.requirements.gpu is None
+
+    message_dict["content"]["requirements"]["node"] = None
+    try:
+        _ = create_new_message(message_dict, factory=InstanceMessage)
+        raise AssertionError("An exception should have been raised before this point.")
+    except ValidationError as e:
+        assert e.errors()[0]["loc"] in [("content",), ("content", "__root__")]
+
+        error_msg = e.errors()[0]["msg"]
+        assert (
+            "Node hash assignment is needed for PAYG or Credit payments" in error_msg
+        )  # Ignore "Value error, ..."
+
+
 def test_message_machine_port_mapping():
     message_dict = {
         "chain": "ETH",