I would send him the money back,as well. I would nicely explain to him that I understand he is having a rough time right now. And that you want to refund the money to help out a little. Also kindly explain that you can do business in the future after he gets settled. That way you sound like a real good guy, which will help your rep. In all likely hood you may never here from him again. However you will have done more than your part.