If you feel that the timing of the economic turmoil this year has treated you shabbily, then perhaps you should talk to Alexandra Eavis and Andrew Meikle. They paid £5million for their Grade I listed Georgian townhouse in Bedford Square, Bloomsbury, in December 2006, just as the first murmurings began of a slowdown in the property market.

Having put down every penny they could lay their hands on, including a £4million bridging loan, to pay for the house and fund a £3.5million renovation job, their builders started work on the house in late summer of 2007, just prior to the Northern Rock debacle. To round it off, the whole job was finished and the house was put on the market last month for £15 million, during the on-going turmoil in the money markets. Did this chain of events have the couple reaching for the vodka and the valium? “Not at all,” says Meikle, who is 49 and runs his own financial services company with Eavis, 30, pictured right. “I'm used to living my life by the turn of a card. It has been fun.” Originally the couple planned to live in the house, and it was only halfway through the renovation that they changed tack and decided to treat it as an investment. Meikle has been in charge of finance; Eavis has overseen the “aesthetics”. Indeed buying the house in the first place was her idea. “I fell for it the moment I walked through the front door,” she says. “That lovely Georgian staircase is so elegant - I could imagine Audrey Hepburn floating down it in a cocktail dress.” Eavis was not even put off by the state of the interior. As with most of the properties in Bedford Square, the house - pictured, middle, above - had for the past 70 years been used as offices and every room bore witness to its past life. “There was hideous dark green carpet everywhere, the rooms were divided by brown glass partitions and there were suspended false ceilings,” she says. “Worst of all were the staff toilets and the disgusting kitchen, left as they were the day the office staff moved out.” However, Eavis realised that most of the work needed was cosmetic rather than structural. Also, she was, effectively, buying two houses for the price of one. The main house was joined by corridors to a 1970s-built mews house at the back and that, she thought, would make a perfect office. The flat above she planned to use as staff accommodation.

The couple were hit by two setbacks before work could even begin. First, it took longer than expected to obtain listed buildings consent because an historical survey had to be completed. Then, in February 2007, squatters broke into the house. Luckily they put up little resistance when the police evicted them and little damage was done. “Just a few anarchist posters and some slogans on the walls,” says Meikle. “But it was worrying at the time.” The finished renovation is impressive. There is a sitting room and dining room on the ground floor, where the couple have installed three Georgian fireplaces costing £30,000 each. On the floor above there is a stunning drawing room. It has a high ceiling and is divided by an arch, triggering another “Audrey Hepburn moment” for Eavis, who has made this the showpiece reception room, laying the floors with expensive Parquet de Versailles. On the two top floors there are four large bedrooms, each with its own bathroom. Corridors on two levels lead to the mews house but, curiously, there is no sense of being in a separate building. One part of the property fits easily into the other, linked by smart little garden terraces in between. In the modern part of the house Eavis, released from the restrictions of the Grade I listing, has been more wildly imaginative. The handmade Italian kitchen has a crescent-shaped breakfast bar; there is also a new swimming pool and gym, a media room and a smart, minimalist office.

As an investment, the property is far from being a disaster. The house might not have a postcode with the kudos of, say, Mayfair or Belgravia, but Meikle reckons that if the house were in one of those areas its price would be more than £20 million. With its lovely garden square it looks rather like the film set for Mary Poppins and it is well located for trips into town. “Last week we went to the Royal Opera, stopping off for a meal at Arbus in Frith Street, Soho, on the way home and walked the whole way,” says Meikle. “It is delightfully quiet here, yet we are right in the heart of the city.”

As for its likely value, Lucian Cook, director of research at Savills, says: “A great number of the people who can afford to buy at this price in Central London are international billionaires with accumulated wealth who have not been unduly affected by the recent economic crisis. Demand for these über-prime properties is still strong.”

Where do the couple intend moving to next? “I'd like an apartment in London and a finca in Majorca,” says Eavis, unhesitatingly. Meikle, however, has other ideas. “I quite fancy another renovation project,” he says. “I hate the thought of putting money in the pockets of developers when I could do the job myself.”

Details: Knight Frank, 020-7483 8349 and Beauchamp Estates, 020-7499 7722

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