The two government-chartered companies that provide most of the money banks and other lenders use for mortgages have increased their fees for loans to borrowers with poor credit.

Fannie Mae and Freddie Mac now charge a full point for consumers with credit scores below 680, up from a half-point.

That means lenders must pay $1,000 for every $100,000 you borrow to have the two companies buy your loan, package it with thousands of other loans and sell it to investors.

Though lenders are certainly going to pass that cost on to borrowers, they probably won't demand the money at closing.

Most probably will look to recoup the cost over three to five years by adding about one-eighth of a point to your mortgage rate. That would increase the typical monthly payment by about $8 for every $100,000 you borrow.

The best way to avoid that kind of expense is to boost your credit score up toward the national average -- 723, according to the Fair Isaac Corp., which developed the most widely used scoring system.

Don't be taken in by credit repair companies.

They often claim to have a special relationship with the credit bureaus that allows them to have legitimate reports of unpaid bills or late payments deleted from your history.

But they don't. And they can't. They're a rip-off.

Our 7 smart moves to improve your credit score will show you how to do it right.