People are being urged not to employ traders who call at their property looking for work without an appointment.
The warning from the Isle of Man Office of Fair Trading (IoMFT) comes after recent storms damaged properties presented traders with an opportunity to offer unsolicited work.
The office is asking people to remain vigilant and look out for vulnerable friends, relatives and neighbours who could fall foul.
Cold calling traders can be very persuasive and sound appealing by offering cheap quotes and quick start times.
However, the office says this is often achieved using poor quality materials and leads to sub-standard work which is not guaranteed.
People who operate in this way can be persistent and will not take no for an answer even when the suggested work is not needed.
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