Not along ago, few people had even heard of a short sale, which occurs when the bank agrees to discount the loan balance for a seller who owes more on his mortgage than the home is currently worth.

If you're in the market for a home today, you're almost guaranteed to be looking at some short sales. Nationwide, 14% of homeowners are currently underwater on their mortgages, calculates real estate website Zillow.com.

The good news is that short sellers are likely to still be living in the home and some may even be current on their payments. That means these aren't the run-down, distressed properties that you often find among foreclosures; in fact, there's a good chance that some of the most deluxe homes for sale in your market are underwater.

Before you get too excited about buying a short sale, know that they generally aren't, well, short. For the sale to go through, the seller's lender must approve the price and agree to take the shortfall as a loss. That extra step can cause the process to drag on three times as long as a normal home sale.

Know what you're getting into. In a short sale, you are dealing with several parties: the sellers, their agent and the sellers' lender. That's why a short sale can take anywhere between two and six months to execute, compared with about 30 days for a typical sale. Though many banks are willing to take a loss on a mortgage in a short sale if it means avoiding an even bigger loss in a foreclosure, with so many owners trying to unload properties, the lender's negotiators are flooded with short-sale offers. So if you're moving or selling another property, keep in mind that you'll likely need to budget for a few months' worth of rental payments so you have somewhere to live in the interim.