Want to sell your home, but not keen on the neighbours finding out? Need to offload your large country house without alerting your share-holders? Welcome to the curious but growing world of “off-market sales”, where deals are quietly struck without a card appearing in an estate agent’s window, a brochure being printed or a “For sale” board going up.

There was a time when only the most expensive houses sold off market, but now owners of far more modest dwellings are following suit – to preserve their privacy or because they believe they will achieve a higher price. The trend has been accentuated by this year’s collapse in both prices and the number of transactions, which has made potential buyers more reluctant to commit and obliged sellers to find more creative ways to shift their homes.

“People from all levels, not just the top end, are trying to sell their house off market,” says Charles McDowell, an upmarket property consultant. “The benefit of this is that your house is not seen to be stale. On the open market, people look through property search sites and see the same old houses coming up. With off-market sales, nobody can see that you’ve been trying to sell for a long time.”

Andrew Findley, a director of Elite Property Search, a company that specialises in the upper end of the market, claims to know of half a billion pounds’ worth of property available privately in the south of England – £200m of it in the Henley area alone. He receives three calls a day from prospective sellers bypassing traditional estate agents in search of one committed purchaser.

“Selling in this way seems to be doing the rounds at dinner parties,” Findley says. “People with nice houses don’t want to waste time keeping the house spick and span just for the bargain-hunters. They don’t have to sell, but would sell if the right person came along – and was prepared to pay the right price.”

Figures compiled by Savills estate agency for The Sunday Times reveal that 46% of properties on its books at £2m or more are only available privately. One, the 2,417-acre Easton estate, in Norfolk, sold last month for £25m. Last year, private sales accounted for 34% of deals; in 2006, the figure was just 19%. Statistics from Knight Frank paint a similar picture, with off-market deals accounting for more than 30% of sales of country houses priced at £2m and above this year (up from 20% in 2007), and 52% for the £5m-plus bracket (39% last year).

So, how does it work? Anyone opting to sell off market will still appoint an estate agent – and will be liable to pay fees in the event of success. Rather than telling the world about the property, however, the agent will pass on its details to a select handful of buyers it knows are serious – or offer it to the growing band of search agents.

Quite how “private” the sale will depend on the price – and, more often, the owner. Celebrities, most recently Jemima Khan and Jasper Conran, and almost anyone who figures on The Sunday Times Rich List, will insist on confi-dentiality agreements being signed by all parties, including prospective buyers.

“There are levels of secrecy,” says Rupert Sweeting, head of Knight Frank’s country department, who reports that only 45% of properties on his books priced at more than £2m are openly for sale. “There are a few sales that only two or three people may know about. Most are just testing the market. We will produce pictures and a floor plan, but no brochure. They want to dip their toe in the market, but don’t want to dive straight in.”

Of these, Sweeting estimates that half will sell, while the rest will either put their property on the open market at a reduced price next spring or wait until prices pick up.

The off-market strategy worked for Gerry Knight and his wife, Gillian, earlier this summer, when they decided to sell Mundys House, a five-bed home in Lower Preshaw, near Petersfield, Hampshire. The 19th-century property, with just under 20 acres, went under offer in February for £5.5m, £500,000 more than the asking price. “It is a unique house and I was asking a premium price,” says Knight, 75, who is now renting a cottage in the county. “If you do that in the open market and put it in Country Life and it doesn’t sell, it gets a bad reputation. I didn’t want it publicly known as an expensive house that nobody wants.” While Knight was not a distressed seller, increasing numbers of those now following his example are victims of the credit crunch. “There are some surprising people coming forward to see if we can get them a buyer,” says Crispin Holborow, head of country houses and estates at Savills. “They don’t want properties aired in public. It can only get worse next year.”

Phil Spencer, the Sunday Times columnist, Channel 4 presenter and director of Garrington, a property-search agency, recently had a call concerning one such sale. “It was a two-bedroom flat in Chelsea that was on sale for £1.6m,” he says. “The owner was about to be repossessed. We were told that they would sell for £1.1m to clear the mortgage if a deal could be done in 48 hours.”

So, will this approach help to flog an average family terrace in the suburbs? “It is not for first-time sellers or owners of average terraced houses, but for more sophisticated sellers,” says Jonathan Hopper, a director of Garrington overseeing the east of England. “It’s less about value and more about the profile of the seller. I know of a £300,000 cottage being sold in this way.”

Not everyone, however, is convinced by the wisdom of off-market selling. “The softly, softly approach doesn’t always work,” cautions Lulu Egerton, a director at Strutt & Parker in Chelsea, west London. “Buyers will wonder about the lack of exposure and why the owners are uncomfortable about going to the market. They will question what is wrong with the house and view the price as too high.”

Additional reporting by Anna Mikhailova

Mum’s the word

Advantages Nobody knows you’re trying to sell the family home or the weekend pad that was once so aspirational, but is now a luxury too far

You can test the market at a slightly higher price: the price you want to get, not the price you’re likely to get

If it fails to sell, you can put it on the market, taking into account feedback from select viewers – and nobody will know that you have reduced the price

You don’t have to keep your house perfectly tidy and styled for viewings

Disadvantages

Many potential buyers out there may never hear about your property

Agents may invest less time in selling your home

Buyers can be put off by what looks like a lack of commitment to the sale

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