SOUTH PORTLAND, Maine (NEWS CENTER) -- Have you ever wondered if the baseball cards that you keep in a shoebox would be better off in a safe deposit box? Collectors had a chance to find out in South Portland this weekend.

Sports memorabilia of all kinds was laid out in a conference room at the Doubletree Hotel for free appraisals by the experts from Clean Sweep Auctions. And if the collectors liked the price they heard, they had a chance to sell.

Some of the treasures that changed hands on Saturday included a Red Sox jersey signed by members of the championship 2004 team, a set of autographed baseball Hall of Fame postcards and a biography of New York Giants manager John McGraw inscribed by his players including Mel Ott.

The slightest smudge or crease can make a huge monetary difference in memorabilia. And sentimental value doesn't always translate into big profits.

Clean Sweep Auctions President Steve Verkman used Tom Brady as an example to explain how changing circumstances can affect the value of sports memorabilia. "It also comes down to signing habits," he said. "Tom Brady is a tough autograph. He hasn't done any big signings. But at some point Tom Brady is going to retire, he's going to have time on his hands. And maybe in five or ten years from now he'll start signing 500 or 1,000 things at a time, and the market will change."

Another round of appraisals at the hotel was booked for Sunday from 9:30 a.m. to 3:30 p.m.