Hi @rafael401
The relationship field will only be able to save data about a post_id, so unfortunately what you want to do is not possible with this field.
Essentially, what you are describing is a relationship from a render to a building with metadata on the connection. The metadata states the room in the building.
I think a solid solution will be to use the posts 2 posts plugin instead of the relationship field.
It is a very flexible plugin which requires good PHP knowledge, but has good documentation so it’s not too hard to get started with it.
That plugin will allow you to create these connections with the extra ‘meta’ data on each connection.
Hope that helps.
