CHICAGO — The auctioneer slides the steel door up, and a small crowd at the storage facility steps forward for a peek.

They are here to bid on possessions left behind when the people who rented the storage unit on Chicago's West Side stopped paying for it.

The bidders are barred from entering the garage or touching its contents, so they stand on their toes to see as much as possible. Some shine flashlights inside, hoping to catch sight of a plasma TV or maybe a leather recliner.

The scene is evidence of an unusual opportunity: Business is booming in the sale of belongings that owners can no longer afford to keep at the nation's storage units. For buyers, it's a grab bag that can yield either junk or the luxuries of a life left behind.

The troubled economy is reflected in the items being sold — trendy clothes, high-end appliances and other indicators that the owners were, until recently, well off.

"What we are selling now is indicative of higher-income people than what we were selling in the past," said Rich Schur of Schur Success Auction Services in Colorado Springs, Colo. "Clearly these are people who fell on hard times."

There's no specific tally of storage unit auctions, but auctioneers say they are busier than ever. Schur's company has seen the number of units it auctions jump from 950 in 2007 to 1,250 in 2008. In January alone, the company auctioned 250 units.

"We are hearing from auctioneers across the country that they are seeing an increase," said Chris Longley, spokesman for the National Auctioneers Association.

Wayne Blair said his Michigan-based business has seen its number of auctions rise about 10 percent in the past year. These days, he's selling off the belongings of customers who have rented storage space for years and until recently paid their bills.

Neither auctioneers nor bidders are allowed to inspect the items until after the sale, meaning they are often bidding blindly.

The reason is simple: Right up until the auctioneer says "Sold," the items are legally the property of those renting the space.

And with tougher times, it's easier to sell the notion that these units could contain what amounts to buried treasure.

"There's a flock of new bidders that show up that heard from a cousin, saw on the Internet that you're going to make a million dollars at auctions," Schur said.

In truth, the dusty boxes often turn up little of value: old clothes, worn-out furniture, worthless documents. Auctioneers continually warn buyers to bid only on what they can see.

Brook Snyder, the auctioneer at the West Side storage unit, said his auctions are typically over in a matter of moments, with crowds ranging from 20 or 30 people to as many as 80.

On one day, a bidder paid $10 for a unit containing a small, old television, a lamp and a few boxes. Another buyer paid $225 for a unit in which bidders could see a washing machine, dryer and lawn mower.

Once in a while, someone gets especially lucky.

"There was one where they bought the unit and moved the boxes and found a Harley," Schur said. "For $400 or $500, they got a unit with a $10,000 motorcycle in it."

Not that the bidders want anybody to know that.