What's the worst that could happen?

[Brandon Phillips]

I see lots of great info and content about creative financing. Especially SELLER FINANCING. Let's say the math pencils out to get a deal with seller financing BUT....let's say the balloon payment is due and the property hasn't appreciated to the point where you can get a loan with a bank to pay out the seller...what are some back-up plan, exit strategies, worst case scenarios?  Any stories, experiences, tips, advice on the matter?