It's important to remember that they don't work for you. Mortgage brokers work for the lender who provides your loan -- and pays their commission.

What that means for consumers is abundantly clear in a new study by the Center for Responsible Lending. The non-profit research group looked at 1.7 million mortgages made between 2004 and 2006 to see if consumers paid more for loans obtained through a broker or directly from a lender.

The center found that borrowers with good credit paid about the same whether they went through a broker or applied directly to a bank or mortgage company. Borrowers with very high credit scores actually fared a bit better by going through a broker.

But consumers with bad credit paid significantly more for a loan obtained through a broker. A subprime borrower taking out a $166,000 loan, paid $5,222 more in the first four years of the mortgage than a borrower who arranged a loan with a lender. Over 30 years, using a broker could cost a homeowner almost $36,000.

"These findings confirm that mortgage brokers steer many of the most vulnerable borrowers to higher-priced loans than they deserve," says Michael Calhoun, the center's president.

Why? Because lenders paid brokers more if they could sell consumers more expensive loans.

"At a time when one out of five families with a subprime loan is losing their home, we must rid the market of perverse incentives that practically guarantee overcharges," Calhoun says.

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