An elderly couple were charged £8,000 for a burglar alarm worth just a few hundred pounds.

The Eastbourne pensioners were bullied into buying the system through repeated telephone calls by a high-pressure salesman.

The shocking bill has prompted trading standards officers to issue a warning.

An East Sussex County Council spokesman said: "Even if you are considering getting a home improvement or security system, no one should be rushed into buying anything, especially over the phone or on the doorstep.

"The initial contact is often by telephone cold calling. Sales people may pretend to be carrying out a security survey in the area and would like to visit your home.

"Once inside, they use high-pressure selling techniques to promote security goods which subsequently turn out to be very expensive."

Other tricksters are reselling clothes donated for charity.

Trading standards advised donors to check out organisations before handing over unwanted items.

A spokesman said: "They are making sometimes hundreds of pounds, money that should be going to worthy causes."

Councillor Bob Tidy, spokesman for community safety, said: "People are pleased to give clothes and other items to charity because they want to help those less fortunate "These deceitful organisations prey on our good nature and do immense harm to the work of real charities."

Trading standards named Olonex Ltd for circulating leaflets encouraging people to donate clothes and other items to help those in the developing world.

A spokesman said: "A check of the leaflet's fine print revealed that Olonex is a commercial organisation and not a charity.

"Now another company, Kraslava Services Seven Ltd, is distributing similar adverts, giving the false impression that anything they collect is for charity.

"Last month, the Advertising Standards Authority warned Kraslava to withdraw its circular but reports suggest the advert is still being used.

"We have received numerous complaints about these firms, including one from a resident who lost a laundry bag with clothes worth several hundred pounds. The resident left the bag out for her laundry service on the same day the bogus charity firm was due to call."

Mr Tidy said: "I would strongly encourage residents to use established charity shops to make donations."

Businesses are being warned to watch for bogus rating experts.

Trading standards said letters of rating revaluation could be expected in the coming weeks.

A spokesman said: "Bogus salesmen claim they can get substantial reductions in rate bills and, after being paid for their services, they fail to deliver promised savings.

"These so-called advisers are usually not qualified and ask for large sums of money as advance payment for each evaluation appeal."