Tycoon forced to sell £20million home after his companies go bust

It is thought to be the most valuable property in London to fall victim to the economic downturn. It was put on the market after multi-millionaire owner Cevdet Caner's companies went bust.

Administrators have been appointed to the Charles Street residence, which is home to Mr Caner, 36, an Austrian citizen of Kurdish origin.

Described as the "enfant terrible" of Austria's financial markets, he is the chief executive of Caner Capital and the founder and majority shareholder of Level One, a Monaco-based property investment company.

Mr Caner bought the house in May last year for £16million. It was at that time described as being in "a tired state". He has since refurbished it at a reported cost of £6million. The total floorspace is 11,250sq ft, including a mews house, pool and garage.

According to a local agent, the administrators are quoting an asking price of £20million. But they have instructed that best bids must be in by 11 December. "The word on the street is that the bank wants to get rid of it," he said.

Mr Caner lives between London and Linz in Austria. His early business ventures were in the call-centre industry. He acquired German call-centre operator Camelot in 2002 but saw share prices plummet from five euros to 26 cents as the market collapsed.

However, he rebuilt his fortune after making the move into real estate with his Level One firm in 2005. Within two years he had created a portfolio of some 28,000 residential properties in Germany, estimated to be worth more than 1.5billion euros at its peak.

Mr Caner, a one-time chairman of Linz Young Socialists, has been involved in financing takeovers of private and public companies across Europe as well as other venture capitalist schemes.

He founded the largest independent customer-care firm in Austria, which is on the Vienna Stock Exchange. But the businessman has fallen victim to the property slump after seeing his real estate companies file for insolvency in September.

In the same month, an £11million house in Holland Park was forced to be sold. Last week a banker, who would not be named, lost his £500,000 deposit on a £3.25million house after failing to make his expected bonus and seeing his stock options fall 70 per cent. Many of London's most expensive housing schemes under construction have seen demand dry up, with no new buyer inquiries for the past few months.

Existing buyers are weighing up whether to walk away from hefty deposits, fearing they could lose even more if they complete at unrealistic prices.