How to choose a burglar alarm contract How to choose an installer

Make sure you get an approved firm to install your alarm

• Don't buy your alarm from cold callers.

• Choose a firm approved by the National Security Inspectorate or the Security Systems Alarm and Inspection Board. Both list approved firms on their websites.

• You can get a cost estimate over the phone, but the company should visit your home to give a more realistic price, including equipment and installation costs. Independent security consultant Graeme Dow said it was ‘inconceivable’ that a company could design an alarm system without visiting your home. Nine out of every 10 companies we called said they would need to see the premises before providing a more detailed price.

• Contact three installers to compare costs.

• Ask for a written fixed price. If they can’t give a fixed price (claiming perhaps that some parts of the job may turn out to be more complex than anticipated), ask for examples of ‘unforeseen circumstances’ that could increase the price. This should limit areas where you could be charged more.

• When they visit your home, reputable installers will ask where the safe is or where high-value items are kept. This may make you uncomfortable, but an Inspectorate-approved company’s staff carry identity cards and will have been checked through the Criminal Records Bureau.

• All maintenance contracts include a basic annual check of the equipment. Some also offer preferential callout treatment; free callouts and a reduced price on repairs or labour should your alarm be faulty.

• Look for how long you are tied to a contract; whether you own or are being leased the equipment (faulty leased equipment would be the responsibility of your installer, although labour costs may apply) and what is included in the warranty.

• Be wary of firms that quote crime figures for your area to sell you an alarm – these are often invented. The Office for National Statistics's website has real figures.