Trading Standards officials stepped in when Linda Gellatly began to have suspicions about the workmen who were fitting a "dry verge system" - plastic capping which claims to keep tiles in place and protect from the rain - to the roof tiles on her Forest Park home.
Mrs Gellatly said that she first became uneasy when she found out that her husband had hired the company after they turned up unannounced on their doorstep – a technique called 'cold-calling'.
Paul Bygrove of Trading Standards, said: "I would advise people to be extremely cautious when dealing with cold callers, and I would also say always get a quote before you agree to getting any work done – this way you can judge if you are being charged unfairly."
Mrs Gellatly says that despite the assurance that she would be given seven days to change her mind about the work, the workmen arrived less than 24 hours later and began to fit the cladding and plastic capping to the roof tiles.
Linda said: "I felt quite vulnerable and pressurised by them when they arrived to start the work. I was here on my own looking after my young grandson."
Alarm bells started ringing for Linda when she realised that the company kept varying the price that they would charge her, and they insisted on a cash payment of several thousand pounds.
Linda decided to call a halt to the proceedings after deciding that the workmanship being done on her house was not of a good enough standard, describing it as "shoddy". She has also discovered that the address provided by the company is an empty unit in England.
The workmen then left debris in the family's driveway, including sharp nails and large pieces of plastic and covering. Linda said: "I had to go out and pick up all of the nails because I was worried for my grandson's safety."
She added: "I'm worried that older, more vulnerable people will get taken in. This isn't a proper company; there were just so many inconsistencies. To be honest, I'm quite upset about it."
Mr Bygrave agreed with Mrs Gellatly. He said: "These people do tend to target older people. Neighbours and relatives are advised just to keep an eye out for anything suspicious, and if they are worried they should contact Trading Standards."