Since you would only be able to rent your condo out for a little more than half of what you owe between your mortgage and monthly condo fees it would be best to determine if your budget can withstand still making the HOA fees and a payment to wherever it is you will be moving into.
Decide if you wish to take the loss upfront now by selling or wish to continue to have to pay for 2 places plus the taxes on each if you plan on purchasing again. Can your monthly budget handle it? Could you make up the loss to your lender if you were to sell or would you have to negotiate with the lender to sell the condo short? A short sale does impact your credit score but not as much as if you were to default on your loan.
I suggest that you consult a tax accountant to determine what your monthly expenses would be and base your decision knowing those figures.
Prudential Connecticut Realty