Now its odvious that your BAH isn't going to cover it/QUOTE]
Might be a math problem. Realistically, PITI for a $400,000 house will be about $2400 to $2500 each month. Add utilities you are looking near $3,000. Were I your loan officer, I would require that you have a gross income of $110,000, after any other debt service (credit cards, car payments and etc) were subtracted. As your realestate agent, I would explain that to get that low rate of $2400, you must put down 20% or $80,000 and explain that your closing costs are going to be about another $20,000. Soooo, about $100,000 to close the deal.
Now you are going to PCS in about 3 years, so if you sell, your are looking about about a $30,000 cost of selling (RE Agent fees, taxes, and etc) To break even, you should be looking at selling for the plus side of $450,000.
Anything less, the delta will come from your pocket at closing. You could keep and rent, but your would need to rent for near $3,000 a month just to have a neutral cash flow, before tax considerations.
There is an interesting aspect in the current housing market, mostly nationwide, with a few exceptions, that is, rents have been keeping pace with inflation, if that, but house prices have far out paced inflation.
Just food for thought.