Audi A2

The A2 is my ultimate example of the benefits of downsizing, with its prestigious badge, solid build, minimal running costs and Tardis-like interior.

While the Audi’s looks don’t appeal to everyone, get past those and you’ll benefit from at least 46mpg from the entry-level 1.4 petrol car, or at best 65.7mpg from the fantastic 1.4-litre TDI diesel. The latter emits 119g/km of CO2, so road tax costs £35 a year. Brilliant!

The only trouble with diesel A2s is that dealers and owners know how good they are – and price them accordingly. I dug up this 2002 1.6 FSI with only 42,000 miles. It’s not as cheap to run as a diesel, but at £6,500 it looks great value. And there are lots of them on the market. Plus, you can still cut your bills in the petrol Audi. The 1.6-litre is good for 47.9mpg, while its 144g/km emissions mean £120-a-year road tax.

If you do plump for a diesel, watch out for worn turbos on abused cars – the A2’s bonnet can only be opened at a dealer, but excessive black exhaust smoke will give the game away. Parking damage can be costly to repair, too. Still, the boot has more space than a Ford Focus, at 390 litres – even though the Audi is only 3.8 metres long.

If you must have a diesel, a high-mile A2 starts at under £4,000. Who needs a big car?