For years, the best way for an overly enthusiastic fan to take home a piece of his favorite celebrity’s trash was to root through the cans outside of the star’s home. Not anymore. These days, storage center auctions are the hot ticket for retrieving discarded treasures; who could forget, in 2007, when Paris Hilton had her bank records, home videos and diaries auctioned off and then displayed on a Web site.

For thousands of people who keep their own belongings in such units, the prospect of an auction is terrifying. For those looking to snag forgotten goods—a celebrity’s or not—on the cheap, the thought is enticing. So how is it these auctions even come to take place?

“The spaces go into auction once they default on the contract signed with the facility,” says Justin J. Manning, president and chief financial office of Storage Auctions USA, a Yarmouth Port, Massachusetts-based auction company. “First there is usually a phone call or notification from the store manager to the debtor, once payments go into arrears. Then the facilities are required to send certified notification to the debtor and also publish a legal notice in the paper, [although this] varies by state. So, the only way someone would be [at risk of having their items go to auction would be] if they stopped paying their storage bill and then buried their head in the sand or changed addresses without notifying the facility.”

While most people wouldn’t want their private items going up for sale, when they do it gives buyers a chance to make a killing. John Cardoza, owner of Storage Auction Experts in Turlock, Calif., warns that although auctions are “only slightly up” in recent months, that’s no reason to ignore the possible deals.

In order to find out about the auctions, he recommends: “People can look in their legal notices of their local paper. Some buyers will call the different storage sites and ask the managers when the next auction will be. Storage Auction Experts put all of our auctions on, a free service for auctioneers to list their auctions. Storage Auction Experts also has a Web page anybody can access. We send out [listings] via US Mail to our buyers for a $10 a year subscription rate to help cover expenses.”

And while not every auctiongoer will make off with, um, priceless goods like Hilton’s lot contained, there is a chance that the lot you do buy—generally entire units are sold at once and not piece-by-piece—will turn out to be worth more than you bargained for.

“[In] June of last year, we sold a unit—10x20 feet—full of comic books,” says Cardoza. “We had around 25 people at this auction. The unit sold for $9,100. What nobody knew was behind the X-Men comic books was a lot of rookie baseball cards. The buyer sold 15 of these cards for $10,000.00 a piece to a buyer who flew in from London. In the back of the unit was some original artwork by Charles Schulz, the creator of "Peanuts.” His insurance broker insured the items for $1.5 million.”

Still, this is the exception and not the rule when it comes to auctions. “Most of the sites require that the buyer take everything from the auctioned unit. So, the buyer can't cherry-pick what items they want. If you want the Craftsman Tool Chest, that's fine, but you are taking the bags of clothes and old mattresses as well,” says Manning. “You can definitely find diamonds in the rough, but you must be persistent and travel and bid on many units.”

With holiday shopping season already in full swing, some buyers might want to take a chance on storage auctions to deliver big-ticket gifts, but managing to walk away from one of these transactions takes savvy, skill and luck.

“There are a lot of items that could be used for Christmas shopping. However, most of the items are used and buying a whole unit at once is probably too much for the average person,” says Cardoza. “For the majority of people, storage auctions would not be a good place to shop.”