My Brain Hurts- Help Me Sort This Out?

Being an adult is hard, yo.

Aside from having to do ALL THE THINGS and now being the proud owner of a second practice, we're trying to sell our house and build another one.

This raises SO MANY QUESTIONS.

And, you know, why have a blog and not make the Internetz answer these questions for you?

So we're building this house, right? And it's coming in about 50K more than I would like it to, which is manageable even though it's extra money per month. Anyway to not spend that money, however, would be stellar.

This leaves me with a conundrum. The community we're building in allows garage apartments. If we have a garage apartment, we can rent it out for about 1/2 of the mortgage payment. It adds about 60K to the price of the house and about $400 to the mortgage each month but we would get nearly three times that in rent if we were to successfully rent it out each month.

There is always the question of whether we would be able to rent it out or not, but with a medical school walking distance away as well as three hospitals, I can't image there will be a paucity of renters.

Do I want someone in my space? I mean, the apartment would have an outside entrance, so he or she should not have access to the yard or my house, but it is a fairly close proximity to a relative stranger.

I think we should just go for it and take the risk, but it's a big risk to take, and it's a lot of money to borrow over and above to 20% down.

What would you do?