Homeowners are offering rich pickings to burglars this summer, according to a study by insurer Norwich Union.

According to them burglars are set to cash in to the tune of £750 million after careless British homeowners leave millions of keys lying around their homes.

With doors and windows being left open in the hot weather and homes sitting vacant during the holiday season, burglars could cash in on a one-stop-shop - stealing on average £2,405 worth of contents and cars per household.

The 2006 Cash for Keys report, compiled by Norwich Union Insurance, reveals 80% of Britons have up to five sets of keys in their home, with half (50%) of people keeping them all in one place. To make matters worse, one home in eight (12%) puts labels on keys, giving thieves a helping hand with clear directions for a fast hit.

Norwich Union Insurance has teamed up with ex-burglar, Bob Turney to gain an insight into the habits of UK burglars. Having spent 18 years honing his stealing skills before changing his ways to become a probation officer.

"The most obvious places to keep keys are the worst places, yet Britons continue to use them without much consideration for how easy they are making it for burglars," said Bob.

• Eight out of 10 Brits (83%) give out spare sets of keys
• A third give keys to their neighbours, thus setting burglars up for multiple hits on the same street
• Nearly a quarter (22%) have handed out sets of house keys to people such as plumbers, electricians, gardeners, cleaners and babysitters and never got them back.

Despite government and police campaigns to encourage vigilance and prevent opportunist burglaries, many people don’t take the risk seriously. Two out of five (40%) of Britons still think they will outwit thieves by hiding a spare set outside their house in case they lose their keys. Some women (6%) even admit to stashing keys in their rabbit’s hutch.

With improved security, car theft is now an increasingly tricky business so thieves are turning their attention to stealing vehicle keys from homes instead. If keys are kept within sight or reach of windows and doors, burglars use "smash and grab" tactics that take a matter of seconds. While the more discerning burglars go for the "hook and cane" method – fishing for keys through letterboxes or cat flaps with a hook or magnet attached to a stick.

Of course once they’ve got your car keys they can not only steal your wheels but load all your belongings into the back of your car and drive away!

This is exactly what happened to Tory MP for Monmouth, David Davies. Thieves broke into his home, stole the keys from the kitchen and then drove off in his car.

Celebrity homes have also been burgled specifically to steal keys to prestigious cars worth thousands of pounds.

England footballer, Frank Lampard was robbed of his Mercedes and Aston Martin last year which had a joint value of £195,000 and Boy band Blue’s Duncan James’ BMW, worth £44,000, was stolen when thieves broke into his family home and located the keys.

Last month, Arsenal’s Patrick Vieira and his family were gassed by burglars who then drove away with his £40,000 Mercedes and valuable jewellery.

To help Britons keep their homes and cars safe this summer, Bob Turney offers his insider advice and top tips:

• Out of sight, out of mind – don’t leave valuables visible through windows and doors. Burglars are like magpies; if they see shiny things they won’t be able to resist snatching them!
• Don’t key clump – don’t keep keys that unlock cars, sheds or neighbour’s homes on one fob
• From handbag to house – if you keep your keys in your handbag, make sure there is no link to your address. If it’s stolen or lost, it makes easy pickings for thieves who will get their hands on a lot more than the contents of your handbag
• Tool kit for stealing – if you have a shed or garage with gardening or DIY tools in, make sure it’s locked at all times. Burglars will look out for tools to help them in their task, so don’t make it easy for them
• Cover your contents – burglaries are a sad fact of everyday life; take all the precautions you can to safeguard your home, including insurance from a reputable company. It will give you peace of mind that, in the event of a burglary, your belongings are covered.

Paul Redington, claims manager from Norwich Union, said: "The research findings have highlighted some pitfalls in home security allowing thieves to cash in on a jackpot of keys, that literally open the doors to cars, motorbikes, garages, safety deposit boxes and neighbours houses."

"Home owner should ensure all windows are shut when ever they leave their house. When on holiday, the house should be left secure and we would advise limiting the number of people who know your home will be left empty for this period of time. Most importantly, lock car and spare keys in a secure place during you holiday."

"We would urge people to review their home insurance policies to ensure they have sufficient cover in the event of a burglary, but if they take the advice of ex-burglar Bob Turney, they could prevent it happening in the first place."