While there is no harm in attempting a short sale because if you do not like the terms in the end you do not have to agree to them, we would of course recommend obtaining legal advice on the various alternatives to consider. All of these are unique to your particular situation, but generally there may be a few different options to consider you should know about.
A Revised Repayment Plan
If you suffer a short-term financial setback (expensive car repairs, a medical emergency), your lender may provide some flexibility by agreeing to let you pay off your deficiency in several installments over the next several months.
A Loan Modification
Many mortgage servicers can adjust the terms of your loan -- most often by lengthening out the amortization schedule of your loan, lowering the interest rate or rolling the deficiency into your loan and re-amortizing the new balance, all in an effort to bring your loan current. No lender wants a mortgage in default.
A Short Refinance
The lender may release you of your existing debt and refinance the outstanding balance into a new loan.
A "Private Money Mortgage" Loan
You may not like the high rates and fees for this type of loan, one from a private lender, but it may allow you to buy time to sell your home in an orderly fashion and avoid default or foreclosure.