Originally Posted by The_Jazz

If you decide to help him, there are some relatively risk-free ways that you can do so and still get paid. The lien idea is one, and you should consult an attorney for others. With the lien, if he stops paying you back, he can't sell or borrow against the property without your consent or knowledge. If he sells, you're automatically first in line for any payment - including in front of him. But there are other options, should you decide that this is something you want to do.

And if you do decide to do it, there's no law, rule or manner that says that you can't charge him interest on the deal. Actually, I would suggest that you absolutely charge him interest.