We're forever being told that new cars aren't sensible ways to invest our money, but predictions from CAP - a leading vehicle valuation provider - published in Auto Express show that you're more likely to get your money back with a Mercedes SLK, Morgan 4/4 or (if your budget will stretch) a drop-top Porsche.

Stuttgart's finest heads the list with its 911 Carrera Cabriolet, Mini comes a close second with the Roadster Cooper SD, and the aforementioned Morgan appears fourth - with each likely to retain between 55.3 and 52.8 per cent of their value after three years and 30,000 miles.

Porsche's Boxster sits at number eight, followed by Morgan's Roadster V6 at nine, while the Mercedes A180CDI AMG Sport, Audi A3 1.6 TDI SE and BMW M135i mark the only hatchbacks in the list. Ferrari's 458 Italia, third, is the only coupe.

At the other end of the spectrum, thirsty saloons are the worst for depreciation - with Volvo's S80 T6 AWD SE Lux retaining as little as 19.3 per cent of its £39,315 list price over the same period.

Only the Proton Savvy auto, Vauxhall Zafira 1.6, and SsangYong's unloved Rodius 270 prevent the list from being entirely made up of four-door models.

However, it's worth remembering the relative prices of each model - waving goodbye to 46 per cent of your Ferrari's £169,545 price tag is still a lot more painful than losing 79 per cent of your Proton's £12,000.