Here's a thought! If renting your property is not an option or if the 25%-30% is not an option, explore a couple of other options. It doesn't sound like you pursued a Short Sale on the property because the lender pays the commission, and is typically the next step when a modification of any type is not approved.
A Short Sale allows the difference or short fall between the new purchase price and the loan amount owed to be forgiven under the Mortgage Forgiveness Debt Relief Act effective through 2012. (Click on link http://www.irs.gov/individuals/article/0,,id=179414,00.html) Assuming you do not have multiple mortgages or liens on your property-which, by the way, you will need to cure, the lender should be willing to allow a Short Sale under the circumstances. A Short Sale can also take a few months to complete, and is subject to lender approval. If you have assets you can liquidate to make up some of all of the short fall then do so in exchange for a "PAID IN FULL" account balance and get it in writing. If you cannot pay cash to make up some or all of the short fall, then it will take two years of great credit management on your part before you can buy property again as I understand it.
If a Short Sale is not in the cards for you then you are left with the option of Deed-in-lieu (of foreclosure) and any short fall also falls under the Mortgage Forgiveness Debt Relief Act. Again consider sweetening the deal for the lender and pay cash to make up for some or all of the short fall; that is, the current market value and loan amount owed in exchange for a "PAID IN FULL" account payoff which will be reflected in your credit. If you cannot pay cash to make up some or all of the short fall, then it could take 5-7 years, may be longer, of great credit management on your part before you can buy property again as I understand it.
I believe the lender just wants to be made whole so being creative and asking for what you want should be on the table. But remember to negotiate a win-win situation for all affected if you can.
These are just suggestions for you to think about. Consult with a Real Estate Attorney.