Over time, houses tend to appreciate an average of 2 percent to 3 percent a year, according to economists with the Office of Federal Housing Enterprise Oversight.

According to Neala Richardson, principal economist with Freddie Mac, the lender puts those numbers a little higher. It calculates that long-range, houses appreciate an average of 5 percent to 6 percent annually.

Also realize that there are no hard-and-fast absolutes. Why you have to borrow is important, too. If you need the money to get you through a tough spot, (job loss, medical needs), weigh your options and tread carefully. If you're borrowing because you lost a job and want to keep the house, that's one thing. But if you want to pay down the credit cards so you can charge them up again, it's smarter (and a lot safer) to slice your spending.

DO reanalyze your investment properties
It's one thing to hang onto a house because rent will cost you just as much each month and you know that your house will (eventually) appreciate. But if you're talking about an investment property and you see signs of home depreciation in the area, then you may want to take another look at the numbers.

"Investor properties are the ones that will be more susceptible to a drop," says Retsinas.

Some things to look at: Can you cover the mortgage? If you have an ARM, will you still be able to cover it if rates go up? Will you make enough in rent to cover your payment? What happens if you have to go a few months with no tenant? And do you have an exit strategy if later the numbers aren't where you'd like?

Smart money: "Rely on the basic economy of the property, rather than perceived appreciation," says Retsinas.

DON'T get carried away with unnecessary improvements
"If you're making improvements, make improvements that will sustain its value," says Retsinas. "Nothing frivolous."

When selling, to get the maximum amount for your house, it has to appeal to the most number of buyers. Increasing rates and buyer uncertainty mean there will be fewer prospects, thus reducing your potential market of buyers. You don't have to put off renovating the kitchen or converting that basement into an office. Just beware of adding extra "frills" or atypical features that could alienate some buyers.

Whatever the home values are doing in your area, you want your home to uphold its highest possible worth. That means keep up the maintenance and make sure it's a clear winner.

"If you're concerned about a down market," says Retsinas, "make sure your property, your home has something to offer that will make it stand out."

Dana Dratch is a freelance writer based in Atlanta.