Consumer watchdogs are warning the public about cold-callers who offer to sharpen tools.
The Office of Fair Trading says the calls are targeting workshops and construction sites.
The OFT is aware of at least two men in a French-registered vehicle who are currently working on this basis in the island.
Chief inspector of Trading Standards John Peet said: ‘It may be that the gentlemen concerned are offering a genuine service but it could also be a scam, possibly involving VAT.
‘I understand that they can be very pushy so make some basic checks before you employ them. Have they got work permits? Do they have a genuine VAT number?
‘Make sure that you agree to a price that is a quote rather than an estimate as they may come back with an extortionate bill.
‘Anyone approached by these gentlemen is asked to contact Trading Standards on 686500.’