Local authorities should do more to prevent private companies taking advantage of the right to buy, the government has said.
Some finance companies are charging as much as £2000 for obtaining and filling out the necessary paperwork. Councils provide this service for free.

Councils have sought to challenge such companies on the grounds that their publicity material contravenes trading standards rules. But between 1999 and 2001 only five cases were upheld on the grounds that the companies had issued deliberately misleading advertising.

A spokesperson for the Office of the Deputy Prime Minister said: "Adverts are within the law so long as they don't misrepresent the truth by claiming that the right to buy is going to be axed within weeks.

"Trading standards have been invoked in the past, but it's really down to the local authority to make sure tenants know they can get help applying for right to buy."

Leaflets with provocative slogans such as "Stop Paying Rent" and "Council rents Will Rise!" have been circulated recently in areas of Oxford. But the council admits that little can be done under the current law.

A spokesperson for the council said: "Although selling these services is not against the law, I would urge tenants to look for help and information before they consider paying anyone."