Well, now that it is established that you can build such a structure, I need to share with you from the sad but true file. A friend built a living area over the barn. Truly, I do not know how it was built or by who. What I can tell you is that for some reason the structure went ablaze one night with disastrous results. As you are looking to have this house guests in the future, one thing to look carefully into is the electric.