Property: A pot of gold under the kitchen sink: It pays to get a second opinion when selling off the contents of the family home, writes David Lawson

THE VALUER examined the box of china. It just might make a small profit at the local auction in Devon, after fees and the cost of driving there had been deducted, of course. A few weeks later the same box of china raised almost pounds 800 from eager buyers in London.

Sue Carpenter had refused to accept the expert's advice about her Royal Copenhagen Flora Danica Botanical part-dessert service and Coalport plates. Into the car and up to London they went, and back she came with a big cheque. A pair of oil paintings valued at pounds 50 also made the trip. They fetched pounds 350 from Lots Road Galleries.

The dream of unearthing treasure from a family glory hole attracts millions to television programmes such as Antiques Road Show. Few will experience the pleasant shock of hearing that granny's vase is a Ming worth a king's ransom. But many more modest discoveries are overlooked every day.

With the demise of a generation of pioneering property owners, more and more people find themselves rummaging through their family's belongings. Last year, at least 150,000 homes came on to the market because the owners had died - more than the whole building industry managed to produce. And the numbers will continue to swell.

Every home is a potential gold mine, but nuggets are rarely spotted. Many people left with a full house simply ask the nearest house-clearance firm to cart the contents away.

'That can be fatal,' Michael Perry, of the Manchester-based auctioneer Capes Dunn, says. 'They will over-value what you might think is ordinary stuff, just to impress you. But among the dross will be something worth far more than the overall figure they pay.'

Most large towns have auctioneers who will provide a free estimate of a home's contents, says Marilyn Swaine, who runs her own firm in Grantham. 'Then you can choose what you want to keep and what the rest may fetch at auction.'

Sometimes the furniture and fittings are not worth the cost of shipping to a sale, particularly after the deduction of fees, which can range from 10 to 20 per cent of the price achieved.

People have distorted views about values, Ms Swaine says. Even agents can get excited about a houseful of good-looking reproduction furniture that may be worth relatively little. 'They then dismiss what they consider to be tat, yet this may hide something far more valuable.'

Mr Perry says that he has only once seen a home which had no value. 'But I have often been to places where the furniture may be worth pounds 300, yet I find a teapot worth pounds 400 hidden in a cupboard.' He recalls one dilapidated terrace which had a Fablon-covered dresser in a tiny kitchen. It was 300 years old and sold at auction for pounds 3,000.

Sometimes he is called in after relatives have cleared away what they consider to be worthless. 'I wince when they say they have already thrown away 50 plastic bags of stuff,' Mr Perry says. 'I hate to tell them that we sell old biscuit tins for pounds 75 and corkscrews for pounds 800.'

He makes a point of looking in cellars, even when told they are full of rubbish. Under the sink is another potential treasure trove. 'A lot of people were given Lalique glassware as wedding presents in the Thirties. This often ends up with the flower vases under the sink, yet it can fetch thousands at auction.'

Mrs Carpenter and her husband, Clive, had one major advantage when clearing a rambling West Country rectory: the home was their own. Mr Carpenter is nearing retirement, and the couple plan to split their time between a new motor yacht and a small London home.

Both are accustomed to dealing with property: Mrs Carpenter is a former agent and her husband a senior partner with the auctioneers Allsop & Co. But they knew little about selling 'chattels' - the ancient name still used for home contents.

'All I had to go on was a seven-year-old insurance valuation,' Mrs Carpenter says. 'Even that was useless, as you cannot bank on someone paying the same for a sideboard as the amount for which it is insured.'

She did not want to bargain with dealers and felt a local auction might not attract enough bidders. A sale on the premises was rejected because of the likely damage to expensive carpets and decorations that had been sold as part of the house. So everything was shipped to London. 'I thought I could get a better deal when there were several auction houses to bargain with.'

It worked out quite well: Christie's took the china, silver and some 'very environmentally unsound' ivory inherited from a relative. Bonhams and Lots Road Galleries shared the rest. 'What one did not like I would take around to another,' she says.

But not everything ran smoothly. Mrs Carpenter recalls the day a van-load of bulky furniture was taken to one auctioneer's yard. Most had been unloaded when a disdainful assessor - who had made no effort to help - told them it was not good enough and should be taken away.

Mrs Carpenter's fears that the five-hour journey from Devon to London would be wasted were eased half an hour later when another dealer took an interest in the wardrobes and sideboards. 'If it hadn't been for him, the whole lot might have ended up on the nearest council tip,' she says.

Transporting the contents of a home half-way across the country is not feasible for most people, however. 'I made sure I had nothing else to do for six months but concentrate on getting the best prices,' Mrs Carpenter says.

Others with less time and determination would do as well getting quotes from local firms, even if that means shipping the property to a neighbouring town. 'It is the loading and unloading that costs money rather than an hour's extra drive,' says Ms Swaine, who has satisfied customers returning from across the country.

Letters after an auctioneer's name can be useful: Ms Swaine is a spokeswoman for the Royal Institution of Chartered Surveyors, while Mr Perry is with the other major professional group, the Incorporated Society of Valuers and Auctioneers. Members adhere to a code of conduct and are properly insured. It may not guarantee getting your furniture unloaded on a wet Wednesday afternoon, but at least there is someone you can sue if granny's vase was a Ming, instead of watching helplessly as the local clearance merchant retires to Monte Carlo.

(Photograph omitted)