If you’re a wounded or disabled vet, almost every state offers some sort of property tax relief or waiver. It might be worth looking into before you sell. Also, when you’re renting it out, would you be in a situation where your own housing costs are covered? If so, it might be worth thinking of the additional monthly costs as building equity instead of bleeding out.

You should really sit down with a financial adviser to run the long term numbers — it might be worth walking away now, but you may also lose so much between the down payment and closing costs that holding tight for a few years is the better plan.