First: take the Rapid developer learning path: https://gettingstarted.mendixcloud.com/link/path/38
Second: use the default login, since a custom one doesn't add anything related to your scenario
Third: associate the estate entity to the account/User Entity
Fourth: Constrain the displayed list to “path to user”
fifth: Publish your profile ;-)
What about creating an association between your Estate entity and the Account entity? That should work and is pretty easy.
I really recommend doing some of the learning paths in the academy section. Stuff like this is covered in there.