There are increasing numbers of nearly-new cars appearing on motor dealer forecourts, largely as a consequence of demonstrator vehicles being registered to help carmakers and retailers meet their ambitious year-on-year sales targets.

Knowing just what to pay for these low-mileage cars has always been difficult, but enlightenment is now just a mouse-click away for anyone visiting www.glass.co.uk.

The Glass's Motoring Guide website includes up-to-the-minute consumer values for vehicles bearing the current registration plate through to those up to nine years old.

Consumers can download a detailed valuation certificate that reflects a nearly-new car's mileage, condition and any additional items of equipment. The individual vehicle's mileage, which can have a significant impact on its value, can be adjusted from just one mile up to 150,000 miles. Each certificate features four figures, including three trade-in values that reflect different conditions (Excellent, Average, Below Average), and one forecourt value. Downloading a certificate costs £2.95, payable online by credit card and by other payment methods.

The Glass's Motoring Guide also offers consumers free access to new vehicle price and options data, a new car comparator, and pence-per-mile whole life costs, as well as an up-to-date insight into the UK's changing car market and an insurance search service.

Steve Ricketts, Strategic Business Manager at Glass's, said: "The availability of these nearly-new cars is increasing rapidly, but many prospective buyers are unsure just how close to the original list price they should pay. The used market as a whole is very sensitive to the number of late-plate cars on offer, and the Glass's Motoring Guide website will produce valuations that reflect the impact of volume on prices, helping consumers buy with greater confidence."