• If a workman does call at your door, make sure that the person is who they say they are take a contact telephone number (not a mobile) and say you will call back later to confirm if you want the work done. You can then speak with friends, family or the police about what the workman was offering.

• Ask where they advertise, or if they are listed in the phone book. Also ask for contact details of previous customers then check that the details are true and that they are happy with work that was carried out.

• Don't pay up front regardless of how demanding they are. Ask for a written quotation on headed paper and always pay by cheque genuine workmen will be happy to carry out business in this way. Always obtain at least three estimates for any work that you want doing.

• If you need to have work done to your property, ask neighbours, colleagues, friends and family for the name of a trader who has done good work for them before. Otherwise choose a well-known respected company.

• Under no circumstances, accompany traders or other callers to building societies or banks in order to withdraw cash. Do not keep large amounts of cash in the house. Bogus property repairers always demand cash and will not accept cheques or credit cards, which give you an opportunity to stop the money being taken out of your account.

DS Chapman said: "Ultimately our advice is never to allow any casual caller do work on your property, be it roofing, tarmacing driveways or gardening. Our message is to keep a look out and if you see or suspect bogus workmen are operating in your area please contact your local police station. It is important that neighbourhoods work together to protect elderly and vulnerable home owners."

Consumers can contact the Trading Standards Doorstep Hotline to report a trader or obtain advice.

see Contacts Page (crimelines).