BMW M635 CSi
You’d be forgiven for thinking the M635 CSi has soared into the price stratosphere after one sold for a record £100,100 at Silverstone’s NEC sale earlier this month – but while prices have risen, most are still within reach. Typically you’ll pay nearer to £20-25k for one in reasonable condition, but that’s still considerably more than the £10k the same car would’ve cost back in 2002. However, given the car’s sale performance at recent auctions, buy one sooner rather than later. They are literally doubling in price.