Your basement is his business. So is your attic, your garage and your storage unit.

Adam Hersh makes his living selling your cast-offs, whatever you own that's too valuable to donate but too much work to sell yourself. In what one person called a "21st century pawn shop," Hersh takes your items and sells them for you on eBay, the online auction house, earning a commission for whatever is successfully sold.

Consignment-by-eBay is nothing new; for years, individual sellers have made extra cash by auctioning items for others. But Hersh, who lives in Manhattan and grew up in Jericho, has one of a growing number of businesses devoted to taking the effort out of listing items on eBay for you by doing the work themselves.

Hersh's business, Adam Hersh Auctions, exists mainly as an online operation, but others - including a few California chains - have opened storefronts as eBay "drop-off" locations.

"Even after my commission," Hersh says, what the client gets back "is about the same as what you'd get if you did it yourself. Even if it's a little less, I take all the hassle away." Trading assistants like Hersh also point out that they know the ins and the outs of auctioning online, including setting up the best photos, descriptions and payment methods. They also monitor the items on eBay and take care of shipping.

Hersh, 25, began selling items for others on eBay four years ago, and now has made it a full-time business, serving customers from offices in Manhattan, where he employs three full-time data-entry workers. No one brings items to him; instead, he and a network of contractors go to clients' homes to take the photos and write the descriptions of the items for placement on eBay's site.

Some other companies say they're planning to open drop-off locations in the city, but Hersh said the potential competition doesn't concern him. He notes that it's easier for him to go to clients than for clients to lug their items on the subway, bus or cab to a drop-off point.

Drop-off locations are popping up in several spots in California, where two main competitors are battling for customers. San Carlos, Calif.-based AuctionDrop has four stores in the Bay Area and handles about 5,000 items a month, said chief executive Randy Adams. It works on a hub-and-spokes system: Customers drop their items off at satellite stores, which truck the goods to a central warehouse for cataloging and storage. The company, which has received about $6.5 million in venture capital, hopes to develop a similar system in the Los Angeles area early next year and expand into the New York area "before the weather gets warm," Adams said.

QuikDrop, based in Costa Mesa, Calif., has nine locations in seven states and aims to sell enough franchises to reach 200 in 18 months, said its co-founder, Jack Reynolds. It has been given governmental approval to open franchises in 38 states, not including New York, where it's still seeking permission. Customers who visit the stores drop off what they want to sell, and if it's sold, QuikDrop keeps a percentage.

In the Hicksville offices of Michael Banks and Rudy Stein, a 1970s-ish multicolored patio umbrella leans against a hallway wall; out-of-place dining room chairs line one room; discarded computer equipment sits on the floor of another; and dozens of neckties sit atop a pile of boxes. Banks is the one who likens the operation to a modern-day pawn shop, and it's an apt description of Online Auction Service & Internet Specialists, the pair's business.

Banks said clients offer plenty of reasons why they come to him. They don't know how to sell an item on eBay. They're too busy to sell it themselves. They've already advertised it in the newspaper and it didn't sell.

Banks and Stein, both 30, usually charge $15 to list the item, regardless of whether it sells, then take roughly 20 percent of the selling price. But the percentage can vary depending on the value of the item.

Banks said he has auctioned items for others for four or five years, at first partnering with shipping and packing stores. Earlier this year he partnered with Stein, with whom he had gone to high school and who also was an eBay seller. In March they opened their Hicksville store, near the Long Island Rail Road station, but they're considering moving to a location with greater visibility.

Since the March opening they have helped individuals and businesses auction off 750 pounds of pillow stuffing, a piano that folds out into a wet bar, a woman's wedding gifts from a previous marriage, a collection of 650 laser discs and a horse carriage from the movie "Amistad." Most of what they sell, though, is "normal, everyday" stuff, Stein said.

"We're the stop before Goodwill," Banks added.

For two years, Long Island Kawasaki-Yamaha in Hicksville has turned to Banks to help sell used motorcycles, said Zeus Xarras, the shop's general manager. He has sold about a dozen bikes on eBay with Banks' help, and while the store had considered eBay in the past, it never tried the auction site until Banks arrived to pitch his services.Xarras said he has sold bikes to people all over the world via eBay, including a bike that no one wanted to buy until he put it on the auction site, where he got $1,500 more than he expected.

"They just come right in and bing, bang, boom, it's done," Xarras said.

So far, eBay is watching from the sidelines, but the stakes could be hefty. The auction site's popularity previously inspired several companies to come up with ways for individual sellers to pay each other using a credit card; when the apparent winner was PayPal, eBay bought the company last year. If eBay consignment services turn out to be the next big thing, brand recognition could be key."This is the future of e-commerce on the Internet," said QuikDrop's Reynolds. "No question."