Foxtons, the largest London estate agent, has been sold for just under £390 million to BC Partners, the private equity group.

The sale of Foxtons, an agency once as famous for its sharp practices as for the fleet of colourful Minis used around the capital by its salespeople, is bound to prompt fears that Jon Hunt, its founder and owner, is making a call on the top of the UK housing market.

House prices in London and across the country have been soaring for two years, but a flurry of data from the Government and lenders has indicated a marked slowdown in house-price inflation since February and raised warnings of sharp slowdowns in price rises in the second half of the year.

Francis Salway, the chief executive of Land Securities, Britain’s largest property company, gave warning last week of a significant slowing in price inflation in Britain’s £710 billion commercial property market. Mr Salway noted that “pockets” of the so-called sub-prime retail commercial property sector had already witnessed price falls over the past six to nine months.

On Friday, Tim Wheeler, the chief executive of Brixton Estates, one of Britain’s largest industrial landlords, told his investors that parts of the UK warehouse sector outside London – from which Brixton has withdrawn – could be hit by price falls because of oversupply.

Mr Wheeler said: “This [industrial sector] supply imbalance and lack of market transactional evidence will lead to underperformance and potentially falling values.”

The sale of Foxtons’ UK business will hand Mr Hunt, its founder and chairman, a windfall of more than £380 million from his 97 per cent share of the business, which includes Alexander Hall, a mortgage broker.

Figures out today from Foxtons show that the UK business had revenues of £100 million. Latest accounts filed at Companies House for 2005 showed pre-tax profits for the UK rose 50 per cent to £12.6 million.

Mr Hunt, who founded the business 26 years ago in an office in Notting Hill, has excluded from the sale Foxtons’ fast-expanding but loss-making US estate agency chain based in New York, which he will continue to control.

Michael Brown, the chief operating officer of Foxtons, will continue as chief executive of Foxtons in the UK under its new private equity ownership.

Mr Hunt said: “Foxtons and Alexander Hall are great businesses. They have grown rapidly and have enormous further potential, because of the quality and depth of the whole employee and management team, the culture of genuine commitment to the customer and the unique operating systems and marketing database we have built. These are the reasons why I have been able to contemplate selling the business I founded and why BC Partners have decided to buy the Group. They share our vision and our commitment to its continued expansion. I am happy to hand over the reins, knowing that what we have started has a very long way still to go and that all my colleagues at Foxtons will continue to prosper.”

Foxtons’ reputation has suffered of late. One rival once described its high-pressure tactics as “hideous”. Last year the UK business and Alexander Hall featured in a BBC undercover programme that suggested underhand sales practices. The programme alleged that the company used fake documents to inflate prices and put forward false offers to sellers. Foxtons denied any wrongdoing but acknowledged that three members of staff had quit and that a fourth had been retrained. Foxtons has since signed up to the industry’s voluntary ombudsman code.

Foxtons has 20 wholly owned offices, 19 in London and one in Guildford, Surrey. Including associated offices, Foxtons trades in a total of 40 UK branches, 22 in London and 18 in Surrey.

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