So lets estimate $400 x 12 = $4,800 a year for 7 years which is $33,600.00; It could goto auction and sell for $70k, now you have a $50k deficency. Best of luck, call me if you need to talk 863-409-1734, i know $400 goes a long ways in this economy, but simply said if you can afford it, keep paying it. Best of Luck :-)
Down the road prices will go back up and so will rent and you will have a retirement income that paid for itself. Why would you want to mess up your credit to get rid of that?!?!?
Lenders want to see a hardship. Doesn't sound like you can prove a hardship and in fact you are in a better position that most people.
Florida is a deficiency judgement state so they can get every penny back from you, including attornney fees, late fees, etc. They can attach your wages to get it once they get a deficiency judgement. Your homestead is probably safe from judgements but not cars, bank accounts, stock accounts (I think retirement funds may also be safe, too).
Lastly if the lender was foolish enough to forgive your debt, they will report it to the IRS on a 1099 as "ordinary income" so you may end up with a substantial tax bill!
You may have to continue to lose about $5k per year... unless you want to just get rid of it and refinance your primary residence to pay the loss on the rental house. Rates are very low, about 4.75% for a 30 year fixed so now may be the perfect time to do that refinance.
Hope this helps.
All the best,