Combination real estate auction and short sale

How do you keep a buyer's feet held to the purchase contract on a short sale when it can take forever to get bank approval on the deal? Through an auction contract that has no contingencies for financing or repairs and requires a hefty non-refundable deposit. We just closed yesterday on yet another auction/short-sale. There were 5 competing bidders at the auction and the buyer remained in the deal through plenty of dramatic ups and downs due to a non-refundable deposit. According to two separate appraisals prior to closing, the auction achieved 98% of current market value. The short sale was approved in 10 days as the bank liked the idea that the final purchase price was achieved through competitive bidding rather than just one buyer stepping forward with a low offer. Buyer and seller are happily moving forward in life. And the referring agent and buyer agent are heading to the bank with their quick commission checks. I love auctions!