That unused spare room is not the only one in the house that can bring in much-needed cash. Indeed, the trend for pop-up shops, restaurants, galleries and clubs, usually in rented spaces, is now being seen in living and dining rooms across Britain.

Jo Wood, who split from the Rolling Stones guitarist Ronnie Wood last year, set up Mrs Paisley’s Lashings, an organic eatery, in the dining room of her Victorian mansion in Surrey earlier this summer. For £120 a head, the likes of Kate Moss and Pat Cash had the chance to sample her home-grown produce — while checking out the decorative scheme she implemented after Ronnie moved out.

Other, more low-key enterprises are proliferating through social networking sites and word of mouth. The chef Gav Tyler and his wife, Alison, both 32, bought their one-bedroom flat in Blackheath, southeast London, for £300,000 in July 2007. “We bought right at the top of the market,” says Alison, a freelance writer, “and now we’re desperately trying to overpay our mortgage each month to dig ourselves out of negative equity.”

To help make ends meet, the pair set up the Savoy Truffle Supperclub, a “dining club” held in their living room. “We’d always thrown big dinner parties, using fresh food from our allotment,” Alison says, “and friends suggested we ask people to pay. It went from there, really.”

Now, once or twice a month, the couple move their sofa into their bedroom and welcome about 15 guests, at three tables, to their BYO dining experience, charging £37 per person. They are registered with the local council as a supper club, not a restaurant, so people can’t walk off the street, but must book ahead.

The food on offer is based around a seasonal, fresh, sustainable menu.

“People love the intimate surroundings and say it is far more sociable than a normal restaurant,” says Alison, who works the front of house. “We have worked out a way to not keep moving all the furniture all the time — the armchairs and lamps just stay where they are.”

While the supper club won’t make them millionaires, they are turning a small profit, which helps with the mortgage. It is also good practice for the future. “We hope to open a restaurant one day, when we can afford it,” Alison says (savoytrufflesupperclub.com).

James Tregaskes, 26, who opened a small gallery in the living room of his family-owned central London flat in March, has also found that intimate surroundings pull in the clients (along with the home-baked cakes and biscuits he likes to offer). First Floor Projects’ first show took place in his small, trinket-packed living room, exhibiting drawings by the Oxford-based artist Lucy Barlow — and about three-quarters of the work has sold, with pieces costing £150-£1,200. “It was extremely well received,” Tregaskes says.

He and his co-director, Hannah Magor, are planning more shows at his one-bedder on Redcliffe Gardens, South Kensington, later in the year (firstfloorprojects.com), and he says he would never take on a stark, commercial place, even if he could afford it: “I would always want to show at home.”

What of the drawbacks? “Well,” says Tregaskes, who has had to move most of his own art collection into storage, “I have to be really, really tidy now. And if you want to run something from home, you have to think about whether you really want strangers coming in. But this place still feels like home to me.”

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