Want a great bargain on a house? Try a short sale – where a lender agrees to take less than the value of the original mortgage just to dump the property.

Fair warning: the short-sale process can be a long, arduous one, and you really have to do your homework Plus, don’t count on banks to be in your corner on short-sales – they’re not such a great deal for lenders. With short sales, lenders are getting less money for the property, and that rarely sits well with banks and lenders (hence the “grumpiness” factor that can come with working a short-sale deal with a mortgage lender).

But if you have the time and have done your due diligence, short sales can be a solid financial move. That said, there are good ways and bad ways to execute a short sale, and knowing the difference can make all the financial difference in the world.

First, some background. Short sales are significantly different than traditional real estate deals. In essence, a short sale is when a homeowner (and the mortgage holder) agree to sell a property at a value that’s less than the amount owed on the mortgage. With the real estate market in decline, and millions facing hardship, whose mortgages are underwater, or who even face foreclosure, a short sale gives them a way out (short sales are particularly less harmful to the seller’s credit than a foreclosure).

Here’s what you need to know to craft a good short sale deal.

Have the patience of a saint – Just because the seller signs off on your purchase, that doesn’t mean the deal is done. The lender has the final say in approving a short sale. And you may find that you have to negotiate your way into a good deal. Jawboning with banks is notoriously a long process – expect it to take up to three months before you have a deal.

Keep your eyes wide-open – Many short sellers are already in dire financial straits, so you won’t get a lot of help from the seller or the lender on a dilapidated property. Factor in the new septic tank or the recently flooded basement into your home purchase budget.

Get an experienced real estate pro – Don’t expect a brand new, wet-behind-the-ears real estate agent who has never experienced a short sale transaction to be much help. Or any help, for that matter. Short sales can be complicated, and, as noted above, they take a while. When you get involved with a real estate agent on a short sale deal, ask how many short sale deals they’ve shepherded along to the dotted line.

Watch for the “two-fer” – Some short sale deals involve sellers with multiple mortgages. If dealing with a stubborn lender on one mortgage is a headache, imagine juggling negotiations with two mortgage lenders. Your options? Dig in for the long haul, or walk away from the deal, and keep looking for a single-mortgage short sale deal. And no matter what, make sure you check with the seller to see how many mortgages – and how many liens - are on the table.

Keep your options open – Short sales take so long, and lenders can be so stubborn over negotiations and keeping you in the loop on any deal updates, that at some point, you may be ready to walk. That walk is much easier if you have another deal cooking on the back burner. Just don’t put any money down before you talk to a lender, and you can take another, better deal that comes along, if the original short sale becomes too frustrating.

Navigating the often stormy, open-ended seas of a short sale is not for everyone. But the reward for the patient and diligent could well be a home that cost much less than you ever thought you would pay.

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