When Tracy Gould agreed to let Silent Witness be filmed in her house, she expected disruption, but she wasn't expecting her son to find a decapitated body in a trunk. "Luckily, he thought it was cool," she laughs.
Ms Gould, a design consultant, has been renting her Wimbledon house out to film crews for the past four years. It has also featured in ads for DFS, McDonald's and Sony. "I started doing it for pin money, but now I enjoy it. I'm selling, but I'm going to look for something that I can use again," she says.
"This house is open-plan so there's lots of space. There are sliding doors and even the kitchen island is on wheels. There's lots of flexibility."
Flexibility is key. You must be prepared for people tramping in and out and moving everything around. Things may also get damaged and you may not even recognise your house when it does appear on the telly.
"McDonald's did an ad here and put up fake walls and filled the place with different furniture. It was nothing like my house by the end," she says.
Film companies are always on the lookout for real locations because it's cheaper than building a set.
The first thing to consider is space. As well as the crew, there is the cast and the equipment, which might fill several trucks.
If your house is chosen, a location team will do several recces before a contract is drawn up. Photos are taken so that everything can be put back where it was. Your room may be painted (and repainted) before you get home.
Tim and Charlie Booth's south London home has been used for many shoots over the past seven years. They're on the books of the agency First Option. "A location agent working on the film Closer looked at it with the director, who loved it," says Mr Booth. "They measured it and rebuilt it brick for brick in the studio. I couldn't believe the level of detail: the fridge and even the ceiling joists were perfect. They used it for the set of Julia Roberts' flat."
But it's the cash, not just movie cachet, that appeals. "For films, the charge is between £1,000 and £2,000 a day," he explains. "The location agents take their cut - 15 to 20 per cent."
When the crew arrives, you leave - for a day, or a week or more, depending on the length of the shoot.
You can expect £500 a day for a fashion shoot, between £800 to £1,000 for an advertising still, and movies can go up to £1,500.
"We have 1,200 locations on our books," says Louise Myers, of Location Works, which has provided houses for Footballers' Wives and Spooks. "Some of them get used a lot, but with others, it's just once. You can't rely on it as an income." Location Works also finds sets for the likes of KFC, Pizza Hut and Marks & Spencer, so it's not all Hollywood glamour.
Location is key. Can you park? Does it look like it could be somewhere else?
Mally Chung, of Chung Locations Ltd,has worked on TV dramas such as Clocking Off and Dalziel and Pascoe. "A lot of filming is done in north London because it's close to Elstree and Pinewood Studios. A crew will try to find locations within a half-hour drive," he says.
He points to another incentive for renting your house out for shoots. "If your house is repainted, you can ask them to paint it another colour," he says. "We've had owners sitting down with our designers and discussing how the room should look. You get professional redecoration advice and the job is done for you."
Sophie Smith and Nigel Edwards, from Stroud Green, north London, have rented out their house twice. "We had 70 people in the house and there were lorries outside providing catering and props," says Ms Smith. "They take over and the trucks can annoy the neighbours. They say it will be a day, but it isn't just a day's disruption. But we love it and would do it again."
Karen Calman, who handed over her keys for a Channel 4 shoot, has words of warning, however. "In the end, it didn't look anything like my home, I don't know why they chose it," she says. There were also accidents. "My parquet floor was scratched and they only touched up the spots on the walls where the paper had been. They also broke one of the doors of my antique cabinet. They paid up for the floor repairs, but I'm still waiting for them to finish mending the cabinet." But she would definitely do it again. "It was £800 to go out for the day. It's not a bad way to make extra money."
There can be other perks, too, says Mr Booth. "We did an M&S shoot once, and they left a fridge full of delicious food behind!"