Rogue traders targeted Rugby residents and tried to charge one victim £4,000 for fixing a few roof tiles.
The unexpected doorstep trader removed some moss from the roof, repaired several tiles and then gave the customer a bill for £4,000.
In a separate incident in the town, one conman charged more than £1,000 for roof repair work.
But the work was carried out to a poor standard and when the consumer tried to contact the trader at the address he had given, he had disappeared.
Warwickshire County Council’s Trading Standards Service is asking consumers and businesses to heed its ‘don’t buy from unexpected doorstep callers’ message after receiving around 100 complaints about doorstep traders.
Warwickshire County Councillor Les Caborn, responsible for community safety, said: “In the past 18 months Trading Standards has received almost 100 complaints about doorstep rogue trader incidents.
“A Trading Standards rapid response team has saved consumers and businesses more than £100,000 during that period, money that would otherwise have found its way in to the hands of doorstep criminals.”
In South Warwickshire, a gang tried to charge a resident £7,000 for resurfacing a private car park.
Warwickshire County Councillor Richard Chattaway, chair of the overview and scrutiny committee, said: “Consumers need to know who the good traders are, which is why Warwickshire Trading Standards is launching its own approved trader scheme.
“Buy with Confidence is a national scheme that provides local lists of Trading Standards vetted and approved traders, giving consumers greater confidence.”