diff.patch

diff --git a/tmt/steps/provision/__init__.py b/tmt/steps/provision/__init__.py
index 772013f..a77ed61 100644
--- a/tmt/steps/provision/__init__.py
+++ b/tmt/steps/provision/__init__.py
@@ -255,6 +255,16 @@ class GuestData(tmt.utils.SerializableContainer):
     # hostname or ip address
     guest: Optional[str] = None
 
+    def from_input(self, obj: tmt.steps.BasePlugin) -> None:
+        for field in dataclasses.fields(self):
+            value = obj.get(field.name)
+            normalize_callback = getattr(self, f'_normalize_{field.name}', None)
+
+            if normalize_callback:
+                value = normalize_callback(value)
+
+            setattr(self, field.name, value)
+
 
 class Guest(tmt.utils.Common):
     """
@@ -621,6 +631,12 @@ class GuestSshData(GuestData):
     # password
     password: Optional[str] = None
 
+    def _normalize_port(self, value: Optional[str]) -> Optional[int]:
+        if value is None:
+            return None
+
+        return int(value)
+
 
 class GuestSsh(Guest):
     """
diff --git a/tmt/steps/provision/testcloud.py b/tmt/steps/provision/testcloud.py
index 43df098..c51c9d6 100644
--- a/tmt/steps/provision/testcloud.py
+++ b/tmt/steps/provision/testcloud.py
@@ -176,6 +176,12 @@ class TestcloudGuestData(
     image_url: Optional[str] = None
     instance_name: Optional[str] = None
 
+    def _normalize_memory(self, value: Optional[str]) -> int:
+        if value is None:
+            return DEFAULT_MEMORY
+
+        return int(value)
+
 
 @tmt.steps.provides_method('virtual.testcloud')
 class ProvisionTestcloud(tmt.steps.provision.ProvisionPlugin):
@@ -278,10 +284,8 @@ class ProvisionTestcloud(tmt.steps.provision.ProvisionPlugin):
         super().go()
 
         # Give info about provided data
-        data = TestcloudGuestData(**{
-            key: self.get(key)
-            for key in TestcloudGuestData.keys()
-            })
+        data = TestcloudGuestData().from_input(self)
+
         for key, value in data.to_dict().items():
             if key == 'memory':
                 self.info('memory', f"{value} MB", 'green')