Stark raving mods

It's time to play the gadget lottery! If you’re planning on personalising your car, you need to think carefully before parting with your cash for extras. Make the right choices and you’ll hit the jackpot come resale time. But get it wrong and you could lop hundreds off the model’s worth.

We all want to give our motors a little character, and aftermarket gizmos are an easy solution. What’s more, they can be a handy addition to everyday life. Satellite navigation or a Bluetooth hands-free kit will prove useful and can make a vehicle more saleable when you decide to put it on the market.

Do your research before buying, as adding a set of gaudy alloys, a performance engine chip and lowered suspension could mean you have to cut your selling price by more than £1,000.

“The majority of motorists are wary of upgrades that are retro-fitted, especially on cars still under warranty,” said Graham Smith of British Car Auctions. “Some modifications reduce your potential audience and deter buyers – this drastically affects the retail value.”

Still, he was quick to point out that not all aftermaket products put off punters. Exceptions include professional factory fit gadgets – and even spoilers, bodykits and wheels from well known tuners, such as AMG or Alpina.

Dealer HR Owen sells Bentley, Ferrari, Porsche and Rolls-Royce models – and it’s at this top end of the market where mistakes are really expensive. “I’d chop whatever I thought the mod cost off the value of a car,” explained the firm’s chief executive Nicholas Lancaster.

“If an ugly set of wheels on a Ferrari was £5,000, that’s what I’d take off the price.” Nicholas added: “My advice is to select products that are popular with buyers, such as sat-nav or subtle entertainment systems.” Check out our panel opposite to see how different extras can alter the value of your car...