Kelly, as an 30 year veteran of real estate in Florida, and as of late doing many short sales, let me tell you what I know.
First of all, the bid depends on whether it is a Freddie Mac or Fannie Mae loan. Unbeknownst to many agents who do not work with short sales, these are government loans and have different requirements than other loans.
If it is a Freddie Mac or Fannie Mae loan, it would be to your advantage to know this as they are only allowed a certain percentage of 'non performing loans' ie: short sales and foreclosures, in their portfolio's or they can not borrow more money from the Fed's, which is where they MAKE their money - by loaning out money at a higher rate than they get from the Fed.
Having said that, a short sale is also looked at by the investors, lender and the PMI company if there is one, to determine the loss of the offer against the cost of a foreclosure.
If I were you, I would contact an agent in your area that is experienced in short sales, foreclosures, reo's, for sale by owners, auctions, and regular MLS deals and pick the one that is the best deal for you. Why limit your options when it is a buyers market, rates are low, and if you are a first time homeowner (or haven't owned a home in the last 3 yrs) there are great tax incentives available for you to buy?
If you need a recommendation on an agent in your area, let me know I've worked in Florida for 30 years and deal with buyers or sellers that I get via internet and have to refer out to a reputable agent in another area, so I can give you a few names to help you out.
Best wishes and I hope this helped.