ATLANTA -- All types of merchants, from mortgage companies to car dealers, use credit histories to determine the interest rate that a borrower will have to pay.

But the credit score consumers pay to see may not be the same one that business use when deciding whether or not to extend credit.

Meet Glen Axlen

Glen Axlen knew his credit score when he went to trade his Ford Expedition in for a new car. He regularly checks his reports with all three bureaus and pays extra to get his scores.

So Axlen said he was shocked when a salesman at a Kennesaw car dealership quoted much lower numbers.

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"I was down 28 points," he said. "My wife was down 55 points."

The drop for the couple spells trouble because the lower a borrower's score, the higher interest rate they pay.

Axlen paid Equifax to obtain his FICO score, and said the dealership used a report from the Atlanta-based company when it perused his application.

The two numbers were not the same.

When Channel 2 Action News called the Ford dealership where Axlen purchased his vehicle, a finance manager there said they use an upgraded product from Equifax known as Auto Finance Beacon 5.0.

Officials at Equifax confirm that account, saying some car dealerships use a different scoring system that was especially designed for automobile financing.

Those scores may focus more on an individual's auto loan payment history, than other data in the credit report.

Axlen is perplexed over why the credit score he has been paying to receive isn't good enough. He said he wants answers.

"I would like Equifax to explain why they charged the consumer $14.95 for a credit report and score that basically was worthless," he said. "As far as I was concerned, that day at that time, it was worthless."

Executives at Equifax disagree.

Robin Holland, a vice president at the firm, said the base FICO score that Axlen paid to receive does have value because it is the one used most often by lenders.

"You need a credit report and credit score to buy a home, to rent an apartment (and) to buy a car so it's important to look at it for that reason," she said.

And yet, car dealers aren't the only ones looking at industry-adjusted credit scores. Some mortgage lenders do, too.

Consumers do have some options, however.

Borrowers who don't like the credit score numbers that lenders see or the resulting deals they offer should take their business elsewhere.

Consumers who don't know their own credit score have no power to negotiate so would-be borrowers should regularly check their reports.