Buying agents used to be the preserve of the super-rich and Hollywood stars who craved anonymity and would not dream of dealing directly with estate agents. But in London, at least, a lack of stock, coupled with sharply rising prices, means their services are increasingly being engaged by people looking for more modest properties.

Jemima Khan, who snapped up an £18m house in Chelsea earlier this year before it even hit the market, may have made the headlines, but it can be just as difficult to find something in the £500,000-£1.5m range — after an extraordinary year in which prices in the capital have risen an average 14%, and 35% in some boroughs.

Marsh & Parsons, an estate agency based in central and west London, has seen a 250% rise in applicants registering to buy, but only a 25% increase in the number of properties on its books since January.

Peter Rollings, the firm’s managing director, is now dealing with 30% more buying agents than this time last year. He says the fiercest competition is for two-bedroom properties in Kensington priced at £500,000- £700,000 and in Notting Hill at £450,000-£600,000.

Cliff Gardiner, head of London for property finders The Buying Solution, agrees. “Looking for cheaper properties is a new thing,” he says. “Everything is selling on or above the asking price. A £500,000 flat is now just as much in demand as a £5m house.”

Gardiner, a self-confessed “poacher turned gamekeeper” (he was an estate agent for 15 years), reports doing 20% more deals under £1m this year, and is recruiting staff to handle this increased number of clients, many of whom are referred on from private banks. Business has tripled in three years, he says.

Lindsay Cuthill, head of Savills’ Fulham office and regional director for the southwest, says: “Three of our deals going through at the moment involve a property finder — the same number as in the whole of last year.

“These days there are rows and rows of million-pound houses. There are 850 alone on the Peterborough estate (in London). If the price is right, properties are going under offer pretty quickly: in a day, a fortnight at most.”

There are now about 150 buying agents in London. But what exactly do they do? “We’re on the phone to estate agents every day,” says Gardiner. “We’re pestering them, so the buyer doesn’t have to. We know what is coming to the market before it hits the shop window or the websites, and we know what is privately for sale.

“Estate agents take us seriously, and therefore they take our clients seriously. People want to become involved in the hidden market.”

This is all done for a fee of course — usually a subscription of £500 to £3,000 — and then 1%-3% of the purchase price. This is in addition to the 1.5%-2.5% the buyer must pay the estate agent to sell their old property.

Before prospective buyers shell out any money, they should do some research. Charlie Ellingworth, who co-founded Property Vision, a firm that finds houses for upmarket buyers, more than 20 years ago, has tips on employing a buying agent. He suggests asking local estate agents in the area that you like which search agents they recommend.

More importantly, he says, you should interview them as you would an agent who is selling your house.

After all, they will be acting on your behalf to get you not just the house you want, but to get you a good deal on it.

If you have already been looking for yourself, test them. Ask about houses that have sold in the area: the agent should be able to say when it sold and how much it sold for.

But is there still a role for buying agents given that it seems prices, especially in London, may have peaked? Even more so, according to those in the business.

“Stock is right down,” says Lulu Egerton, a director of estate agency Lane Fox. “Compared to this time last year, stock is down 50% and inquiries from buying agents are up 8%-10%.

“When the market is squeezed like this, purchasers like to use buying agents to turn over every stone. They want someone to phone the owners of that house in Onslow Square that was for sale last year and ask them if they will sell to them. Buying agents are always more noticeable when the market is like this.”

Be a smart searcher

Househunting can be time- consuming and stressful, but these tips can help you find the home of your dreams.

Check the performance of your local council, from tax rates to recycling fees, at www.audit-commission.gov.uk. Click on “local government” on the right-hand side of the screen, and on the left side of the next page, click “choose authority”. A list of all councils will appear.

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