Going, going, gone - if you're not too greedy

"Turn your chattels into cash," suggests Billy Brown, auctioneer at Under the Hammer. Under the Hammer may not be Sotheby's or Christie's, but this auction house, which opened last November near London's Portobello Road, is one of many house clearance-oriented auctioneers that will sell your unwanted furniture even if it isn't antique.

Imagine that your sofa has got to go. The junk heap is a tragic waste - it probably cost you pounds 1,000 not too long ago. The prospect of paying removal men about pounds 40 to dump it is rather grim.

You could sell it privately with an ad in the local paper or the corner shop. But prospective purchasers will come and take stock - of the sofa, you, your home, your valuables and, if they're lucky, your holiday dates. Another disadvantage is that offers have to be weighed up instantly. When a stranger is standing in your living room with pounds 150 in cash, the temptation is to accept it. You cannot know that the next person would have offered pounds 200.

Selling through an auction house takes away the hassle of exchanging your goods for cash. For a fee, they will come around, pick up your sofa and sell it to the highest bidder. Your only worry is how high that highest bid will be.

"I've seen two identical gilt suites sold, one for pounds 2,300, the other for pounds l,100," says Mr Brown. "Sometimes with two identical lots, one goes in a flash, and the other doesn't. It depends on who turns up that week."

Prices of lots are agreed by the vendor and the auctioneer. Although some people might be lucky to be told that the pine table they almost put on the bonfire should go for pounds 100, many feel they should get more, particularly if they are selling something they bought brand new only a few months ago. "People get very greedy," says Mr Brown. "They don't put themselves in the buyer's shoes. If they insist on pitching the price or reserve high, we'll tell them to go away or insist on a high unsold charge.''

There is a risk that goods might not sell. Under the Hammer usually gives lots six weekly auctions before writing to the vendor to say they haven't been sold. To retrieve your furniture, you'll have to pay an unsold charge, usually pounds 5 to pounds 25. The alternative is to drop the reserve, and get what you can.

All auction houses charge a seller's commission, as well as a buyer's premium. Rates vary from place to place, and are subject to VAT. Under the Hammer charges a minimum seller's commission of pounds 15, or 10 per cent, whichever is higher. This applies not to each single item, but to each instruction form filled in by a seller. So if you want to sell a bundle of items, even if each is only worth a few pounds, it can still be worthwhile.

You should tot up the charges before you start thinking about how you will spend the cash. Minimum commission, VAT and collection fees can take a sizeable chunk out of the selling price of your old chest of drawers.