In 1987 I was one of a few thousand people to cram into the Albert Hall to see a young auctioneer called Robert Brooks sell a Bugatti. In his last job for Christies before setting up shop on his own, he brought the gavel down at £5.5 million on the famed Type 41 Kellner Coupé, a sum that trounced the then greatest amount ever paid for a car at auction. The memory of the gasp and the applause that followed remain with me, 26 years later.

Brooks, in the meantime, has moved on to other things which is why now, as the chairman of Bonhams, he was also able to sell the ex-Fangio Mercedes-Benz W196R Grand Prix car for £19.6 million at the Goodwood Festival of Speed.

There are several remarkable aspects to consider here. First this is not just the most expensive car to be sold at auction, it is by a mile. The previous holder of the record was a Ferrari Testa Rossa sold in 2011 for £10.8 million, almost £9 million shy of the price achieved for the Mercedes. Second, the Mercedes is a Grand Prix car, a configuration that has always struggled to keep up with the prices realised for more usable and user-friendly sports and GT cars. Third, it looks like the car will need a ground up restoration if it is to be restored to its former glories. You may remember this is the car that was gifted by Mercedes-Benz to the National Motor Museum in Beaulieu in 1973 only to be somewhat controversially flogged on in 1980 to become the only W196 to exist in private hands. Its condition is entirely original but not much better than barn find.

Why did it fetch so much? That perceived originality, backed by total authentication by Mercedes-Benz itself, is clearly a massive draw. It is also the car in which Fangio won both the German and Swiss Grands Prix in 1954, so contributing more than any other to his second world championship.

But I think there’s more to it, even than this. I think the W196 marks a departure point where a car is not longer thought of as a mere machine, but a work of art. And in that context, the price achieved is really not that surprising at all.

Even so I wonder how the people from Mercedes Classic were feeling in the aftermath of the auction as I squeezed myself into their 300SLR Uhlenhaut coupé for a run up the hill. This is the W196-based coupé intended to win Le Mans in 1956 that never raced due to Mercedes’ withdrawal from racing at the end of the 1955 season. It is a car described last year by Simon Kidston as ‘the most valuable car in the world.’ So if the Grand Prix car is worth nearly £20 million, what on earth would the more beautiful, more usable and enigmatic coupé fetch?

It’s a question I tried hard not to think about in a couple of runs up the hill – I concentrated only on keeping it on the tarmac and making sure I wasn’t fooled by the weird gearbox gate into wrong-slotting its 3-litre straight-eight Desmodronic engine into fragments.

It is tempting to presume the price achieved for the W196 is a high water mark because cars of that calibre rarely if ever change hands publically. But if these cars are perceived as art and especially if China opens its eyes and doors to such cars, it could just be a start. Strange though it may be to think it, it’s still possible the W196’s mystery buyer may yet turned out to have bought a bargain.

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