Everything depreciates, even Ferraris that drop to between £20,000 and £30,000, then start going up again. So the trick is to buy a Ferrari when prices for that model bottom out. 550s and 575s are now on the way up. Similarly, good 1980s Porsche 911 930s are now going up, and moneyed people have turned older Aston Martins into rapidly appreciating investments.

But any exotic car can turn round and bite you. A new engine for a Porsche 911 or 996 can cost £15,000. Basically the rarest, most desirable cars appreciate, but they also tend to have the highest running costs. The less rare, more reliable cars, like anything with the 6.2-litre Mercedes AMG63 engine, depreciate. It doesn't work both ways.