IT BEGAN with a knock on the door and is ending with a demand for more than £3,500.

Mother-of-three Maria Shwenn wanted to buy her council house but being unemployed, didn't think she'd get a mortgage.

The rep for Diamond Lifestyle who called at her home claimed the firm were experts in council house "Right to Buy".

The result was a mortgage offer at what Maria calls an "extortionate" rate of interest that she rejected.

For its efforts in coming up with this offer, Diamond Lifestyle is now suing her for £2,995, plus interest and court fees.

Maria has since bought her home in Huyton, Liverpool, for £34,220 - thanks to a loan at standard rate from a high street lender.

Incidently, the sole director of Diamond Lifestyle lives in a house in Cambridgeshire he bought for £620,000.

Maria was twice interviewed by Diamond reps. The first time she was told she wouldn't get a mortgage.

The company phoned over the coming months and arranged a second chat after she took a part-time job as a catering assistant.

This time there was good news. She would get a mortgage.

But it was from an obscure lender she'd neverheard of and the repayments amounted to a a massive £3.07 for every £1 borrowed.

The rep, Maria told us, maintained she wouldn't receive a loan from a high street lender.

She tried anyway - and got an offer from Cheltenham & Gloucester at a repayment rate of just £1.99 for every £1 borrowed. Delighted, Maria told Diamond Lifestyle that she wasn't interested in their offer. But the firm still billed her, saying she signed a contract agreeing to pay the firm if it secured an "acceptable" mortgage offer.

According to Maria, all she had signed was a form giving permission for Diamond to make a check on her credit history. And, in any case, the offer was not "acceptable".

"I believe I was duped into signing this contract," she told us. "I am being pursued by these people for money I believe they are not entitled to.

At the offices of Diamond Lifestyle in St Neots, Cambs, we met boss Alan Kempson, 44, as he stepped out of his Mercedes CL500. He insisted the firm's charges were valid because it twice tried to find Maria a mortgage - once before and once after she found work. "This job has cost us more than any other job," he said. "We've done the service we said we would do."

Some rivals would charge as much as £4,000 for this, added Kempson, previously a boss of Computer Re-Sale Limited which was shut down by the High Court over unpaid debts shortly after he resigned.

While we await a court to decide whether Maria should pay Diamond, we'll leave the final word to housing co-operative Tenants First.

It warns: "A number of tenants have alleged that Diamond Lifestyle have used aggressive selling techniques and that it is not always clear to people what they are signing.

"We would strongly recommend that you seek independent financial advice or contact your local Citizens Advice Bureau before you sign anything with a company like Diamond Lifestyle."