It's better to follow the 2% Rule which suggests that you can enjoy the benefits of a home refinance if your mortgage refinance rate is 2% lower than that on your current loan. The interest savings will help you recoup the costs you've paid for the new loan provided you stay in the property for a certain period of time (break-even period). However, there are no-cost as well as low-cost refinance loans wherein the costs are included into the loan. But you can expect comparatively higher rates on such loans. Moreover, these loans are limited when the market is in a credit crunch.
If you plan on moving out of your existing home within the next few years, it may not be beneficial for you to refinance. Make sure you let your mortgage specialist know your future plans.
Be Realistic. Lenders have tightened up loan requirements, so you'll need a good credit score and at least some equity in your home to refinance. To figure out how much equity you have, subtract the total amount that you owe on all of your existing mortgages from how much you think your home is worth. If your credit is severely impaired or you owe more than the value of your home, you probably won't be able to refinance right now.
Don't fall for the 0% apr unless it fits in with your master plan. A lot of brokers will try to get you locked into a low interest rate that will balloon on you in a couple of years and leave you out on the street.