Top Gear Test Drive Directory: don't buy a car without it

It's not a good time to be a motorist. What with expensive fuel and the ever-growing threat of even more expensive road tax, it's enough to make us want to sell our cars.

We won't, of course, since we rely on them too much. So instead we need to make sure the next one we buy, new or old, is the most economical and cost efficient we can find.

This means we need to do our homework like never before - while once all we cared about was whether the GLX specification came with mats and flaps, we now need to know exactly how much C02 each engine produces. You'd be surprised how many fall into more expensive road tax brackets by just one or two grams.

However, we've trawled through list after list of running costs to suggest those that won't be heavy on the wallet, even in the normally tax-heavy SUV sector. Take our cover car, the new Ford Kuga. Thanks to a two-litre diesel it returns a healthy (for a 4x4 at least) 44mpg while road fund tax is a reasonable (again, for an off-roader) £170.

So if you don't want to be left with hefty running costs bills and a car that's in negative equity, do your research now. But thanks to our advice as well as thousands of used car prices from Glass's, by simply buying this issue of TGTTD, you're half way there.