In real estate lingo, a point is one percentage point of the overall loan that is paid up front, typically at the time of closing. For example, if you are borrowing $150,000 on a mortgage loan and will be paying three points, you will pay $4,500 up front. Paying points generally lowers the interest rate on your loan.

When determining whether you want pay for points, think about how long you expect to live in the house. Over a short time frame -- less than five years or so -- paying points usually doesn't makes sense, as you will pay more in points than you will save in interest. However, if you plan to stay in the house for 10 or 20 years or longer, points will pay off over time. Although the prospect of paying a few thousand dollars more initially isn't very attractive, you may be able to save money over the duration of the mortgage.

Another advantage of paying for points on a residential mortgage is that you can deduct the money you pay on that year's income tax return. In some areas, it's customary for sellers to pay your points at closing. As the buyer, you can still deduct the points payment from your taxes, as long as they meet IRS guidelines.

When shopping for a mortgage, factor in your loan with points and see when you will break even. If you see that by paying $2,000 for two points you will break even in 7 years, and you plan to stay in the house for at least 15 to 20 years, you will come out ahead.

Don't confuse the aforementioned kinds of points with origination points (also known as "origination fees"). Origination points won't lower your interest rate, and are called origination "fees" for a reason: you pay them for work your lender does on your behalf. Not all lenders charge origination fees; if your lender does, you may be able to negotiate them down or out of your load entirely.

You can finance points, which allows you to pay them off as part of the loan. But this increases the cost of your points, and it will take longer to break even. If you can, pay for the points in full at closing.