If you took out an adjustable-rate mortgage over the last several years, the low introductory or "teaser" rate that made your monthly payments seem so affordable has probably expired or is about to end.

Your payments are going up, perhaps by hundreds of dollars a month, and you're in shock.

A recent study by a company that collects and studies real estate data predicts that one in every three homeowners who enjoyed an artificially low initial interest rate on their adjustable-rate mortgage will default as the rate and payments rise.

What should you do? If your mortgage rate is over 7%, or it will reach that point at your next adjustment, it's time to refinance.

If you're planning to stay in your home for only a few years, consider an interest-only loan as a short-term fix. It doesn't require you to pay any of the principal for up to five years, so your payments will be less.

If you plan to live there for a while, go for a fixed-rate loan. Mortgage rates for a 30-year fixed are hovering around 6.125% or less right now. That's a substantial savings, and it is the rate you will pay until you refinance again or sell.

No more sleepless nights wondering what your rate will be when your mortgage resets or if you will be able to afford the payments. Your new rate is permanent until you make the change.

To find the lowest rates and determine what your monthly payments will be, use our interest rate comparison charts and mortgage payment calculator.

Refinancing isn't available to everyone however, especially owners who don't have at least some equity in their homes.

It's not cheap either, costing 3% or more of the amount of your new mortgage. So we don't recommend doing this if you are going to move in the next few years because you may not be able to recover the costs involved. Check out our refinance calculator to see if it makes sense for you.

If refinancing isn't your answer, what options do you have? That's the question we posed to eight of the best experts on personal finance we know.

Together, we came up with steps you can take, based on how much your payment has gone up, with the ultimate goal of keeping you out of foreclosure. Some of these steps may seem drastic or tough to accept, but at least you'll have a starting point for taking control of your situation.

Whatever the increase, do whatever you must to keep up with your payments. If you can't pay all your bills, pay the mortgage first. If you don't pay your Visa bill they will take away your card. If you don't make your mortgage payments, you'll lose your house.

IF YOUR PAYMENT HAS GONE UP $100 A MONTH:

Consider yourself lucky.

That's less than $3.25 a day. You should be able to meet your higher mortgage payment without a lot of sacrifice.

Start by examining your daily expenses and see what you can cut out and never miss.

For instance, are you grabbing coffee and a bagel on the way to work, buying snacks from the vending machine or eating lunch out every day?

Change just one part of your daily routine -- eat breakfast at home, skip the vending machine (or buy a 12-pack of sodas and a box of microwave popcorn at the grocery store and take them to work) and take a lunch instead of eating out -- and you'll have the extra cash you need.

Ease yourself into those kinds of changes by making just one or two and implementing them only a couple of days a week. Then gradually increase.

Also, look at your monthly expenses.

Are you paying for premium movie channels that you hardly ever watch? Did you sign up for online services you don't use, such as commercial-free radio or unlimited electronic greeting cards? Cancel them and you'll be amazed to see how much extra cash you'll have lying around.

You could also go online and sell personal items you don't need or don't mind parting with. If you've put all your favorite music on an iPod do you still need the CDs? You can sell them on eBay or Amazon.com, along with books you've already read, movies you've already watched, clothes you (or your kids) no longer wear or collectibles that don't mean anything to you.

IF YOUR PAYMENT HAS GONE UP $200 A MONTH:

If you work at a job that offers an opportunity for overtime, this could be the answer to your problem. The equivalent of one extra shift a week would probably give you more extra money than you need.

If that's not an option, consider taking a part-time job at night or on the weekends. Some folks have used this strategy to pursue an interest or learn a new skill. Are you a morning person? Call your local newspaper to see if they need people to deliver the paper.

Do you have a skill you could turn into a business? If you're a whiz at a particular subject, you could do some tutoring at $30 or more an hour. Do friends call you when their computers have crashed? Hire yourself out as mobile tech support -- the pros get $100 an hour or more. Maybe you make awesome cakes or you throw legendary parties. Get into catering (thatâ??s how Martha Stewart got her start) or event planning. Get the word out by putting a classified ad in your community newspaper (they're really cheap) or on an online bulletin board.

The part to remember, though, is that you need to set aside a portion of what you earn to pay your taxes. The last thing you want is to get hit with a super-sized bill -- and a penalty -- come April 15.

Another possible source of cash flow is your retirement fund. If you've been paying into a 401(k) at work, you could cut back on that contribution. If your employer provides matching funds, do the minimum you need to get that free money. But if the choice is cut back on retirement savings or lose your house, cut back.

IF YOUR PAYMENT HAS GONE UP $300 A MONTH:

You are going to have to raise some serious money. You can free up several hundred dollars a month by eliminating a major expense such as a boat, motorcycle, off-road vehicle, time-share condo, or season tickets to your favorite sports team.

You might be surprised at how much you can save by selling your car or truck and getting something more affordable. If you're driving a big $30,000 pickup or sport-utility vehicle that gets less than 20 miles per gallon you can not only reduce your monthly payments, but spend less on gas and insurance, too.

Instead of cutting costs, how about boosting your income by taking in a renter or getting a roommate? A walk-out basement with a separate entrance or a studio space above the garage is perfect for having a renter, but you can also make it work with a split floor plan with bedrooms on opposite sides of the house. If you live near a college, contact the housing office to post that you have a room available, or run an ad in the local paper or an online bulletin board for a roommate.

If you or your significant other is staying at home to raise kids, you could also bring in some cash by doing in-home day care. Many working parents much prefer having their child in a home than in a daycare facility.

Your home is your biggest asset. Don't put it in jeopardy. Write down every cent you spend every day and every bill you pay and see where you can cut back.

Develop a plan and then stick to it. Your home is worth it.

We developed this advice with the help of:

• Adam Brown, vice president of New York-based Topdot Mortgage
• Eva Rosenberg, an accountant, income tax educator and enrolled agent, which means she's licensed by the U.S. Treasury Department to represent taxpayers before the IRS
• Mary McGrath, a Certified Financial Planner with Cozad Asset Management in Champaign, Ill.
• Bob Walters, chief economist with Quicken Loans
• Eric Rosen, Broker Services Manager for Charter Funding in Rockville, Md.
• Barry Armstrong, a financial planner with Woodbury Financial Services, Inc., and host of "Money Matters," a daily, two-hour, syndicated radio show
• Justin Aldi, CEO of First Security Lending in Burbank, Calif.
• Robert Beal, president of Front Row Mortgage Co. in Atlanta

By Pat Curry

Interest.com Contributing editor

Have a question about your finances? Ask us at editors@interest.com