I second Paul's opinion on this. In most cases it is completely out of the hands of lender. A short sale or pre-foreclosure can take 2 to 6 months (or more) to get a response, so by the time you get a response the buyer's pre-qualification will most probably be expired.
In addition to that the property might have multiple biddings and the final price might be well over the listed figure as the price, in most cases, has not been approved by the bank. That is why close to 90% of them never close. If you add the fact that a property can have more than 10 bids on it, you can see that each individual will have about a 1% chance of actually getting it!
Foreclosures and regular sales are generally way better options!
I have found that Homecomings, National City and HSBC are decent to work with. Some of the smaller ones have been good as well. A lot of it depends on who the negotiator is for the bank, the reason for the short sale and what kind of an offer you are presenting. Keep in mind, a short sale needs some response time. Usually, those who are patient, get rewarded.
I have not found any lenders that are good at dealing with pre-foreclosures or short sales. This is why, in the Phoenix area, almost 90% of these transanctions never end up selling. Save yourself time, effort, energy & money by focusing on REO (bank owned properties) or private sellers not in foreclosure.