What you actually pay is usually up to you and your ability to sniff out and bargain for the best possible deal. Generally, you can obtain the lowest possible rate on your new loan by paying all the loan costs yourself. But you may be able to get some of the fees waived if you return to your original lender. At the same time, though, other lenders might be willing to omit some charges to get your business.

If you are considering an adjustable mortgage, lay out a worst-case scenario. Most ARMs come with annual and lifetime ceilings on increases in either the interest rate or the monthly payment to protect borrowers against what’s known as “payment shock.” But you still want to do the math to make sure you can handle the possibility that your loan could adjust to the maximum as quickly as legally permissible.

The refinanced mortgage could also save you the cost of private mortgage insurance. If you put less than 20 percent down on your original mortgage, your lender likely saddled you with the coverage. If your refinanced mortgage is less than 80 percent of your home’s value today—a likely scenario given current appreciation rates–you won’t have to pay PMI premiums of $50 or more a month.

If you are looking elsewhere, consider your local savings & loan or community bank; a local, regional or national mortgage company; or even a commercial bank. Practically everyone these days is in the home loan field, even credit unions.