Jill, this is not your responsibility. The seller wants to sell. Just as the seller pays the commission for the real estate agent, any non-traditional fees (this is a non-traditional expense) must be paid by the seller, especially due to its highly speculative nature. A short sale is not guaranteed. No need for you to be on the hook for this. Negotiate to have them pay this expense out of closing costs, or walk away. There are too many good deal situations available for you to get into a trap.