It will be up to bank on what they accept. I was a buyer's agent and my client's came in with a reasonable offer, no contigencies, no seller's assist, and about 8 weeks later the offer was rejected. The bank wanted full market value. My buyer's said "goodbye"to the deal and moved on. Some banks are coming around with Short Sales, some aren't. I wish you great luck in your RE pursuit.

Short sales can be tricky and you never know what the bank will say. I'm currently working on a short sale with the buyer getting seller assist and the bank has approved that part of it. If you really want the house, I'd say take a chance and go for it. It can be time consuming and you never know how long it will take to get a response from the bank so you need to be prepared for that. Make sure your agent is comfortable in working with a short sale property or that they have a reliable resource to work with them on this before you go any further.