The Scottsdale round of collector car auctions in January is the bellwether for the classic car auction market each year, and in 2017 there's a particular Mercedes-Benz 540 K Special Roadster that will provide an accurate indication of the robustness of the very top end of the market. It's a rare car, one of around just 25 made, and it has been to auction twice before. It was auctioned during Monterey Car Week in 2011 by RM Auctions for US$4,620,000. It then went back on RM's auction block at Monterey in 2013, appreciating 62 percent in two years to sell for $7,480,000. In Scottsdale 2017, the same car is going to auction again.

Conventional wisdom suggests that although collectible automobile prices are a bit soft in the middle tier at present, genuine top tier cars are still appreciating in value. That hypothesis will be tested because this is unquestionably a quality car – both precedents have shown it to be well inside the top 100 automobiles ever sold at auction at each respective point in time it has been valued by the marketplace.

What is a "Spezial Roadster"?

It is brutally fast, handcrafted, hulking art deco sculpture on wheels designed to seat two comfortably at 100 mph on Germany's autobahn network of the thirties. The 500 K Special Roadster was one of a half dozen variants using the 5.0 liter straight eight with Kompressor (supercharger) introduced in 1934, and in 1936 it was lightened and upgraded to 5.4 liters to celebrate the fiftieth anniversary of Carl Benz's 1886 Autowagon, which kicked off the automobile industry.

The resulting 540K engine produced 115 bhp without the supercharger engaged and 180 bhp when the compressor clutched in at full throttle giving it a top speed approaching 110 mph. When tested by Britain's Motor magazine, the 540K hit 102 mph at the end of a quarter-mile. This performance may not seem that impressive today, but this was incredibly fast eighty years ago. Apart from the speed and beauty, it also has immense presence and you really do need to see one to comprehend how big it is, and how extravagant all that metal seems for just two people. Design head Hans Nibel somehow managed to give the Special Roadster the automotive equivalent of Da Vinci's "divine proportione" because it looks perfectly proportioned in photographs but not nearly as impressive as it does in real life.

Only 29 500 K and 25 540 K Special Roadsters were made, they were frightfully expensive and very few have survived. The image above is from the 1936 Berlin Internationale Automobil Ausstellung (International Automobile Exhibition) in February of that year and shows the 500K Special Roadster.

The car directly above is a replica and was the focus of a 2015 New Atlas feature article entitled "Mercedes-Benz 540K Special Roadster ... going cheap" where we speculated about what it might fetch at auction. Although it was originally built as an almost mechanically-identical Mercedes-Benz 540K Cabriolet B, and had been rebodied by an acclaimed master craftsman, it wasn't a "real one." The atom-perfect 540K garnered a record $1,870,000 for a replica at auction, but as an investment, the purchase price of the Cabriolet B and the cost of the fabrication might well have exceeded that figure. There's a lot more detail on the history and back story to the model in that article, with the most significant new information being that all those other previously not-as-desirable variants (Cabriolet A, B and C, autobahn cruisers, coupes and sedans) are now heading north of $2 million at auction and look likely to exceed the price of the Special Roadster replicas that have been created from them.

Rebodying one of these cars to Special Roadster spec costs a million or more so it probably won't happen any more, and given the rate at which genuine 540 K Cabriolets and other variants have been appreciating, it's entirely possible that sooner or later it might be worth reversing some of those Special Roadster replicas into their original form because they'll be worth more. It is a crazy world.

With the Special Roadster's astronomical in-period price in the wake of Great Depression, only very wealthy people could afford them. Owners in the day included Jack Warner of Warner Brothers Studios, 1930s movie heartthrob Clark Gable (best known for his lead role in Gone with the Wind), Reginald Sinclaire (heir to the Corning Glass fortune) and the President of the German Parliament, Hermann Göring.

Göring might have tainted brand values these days, but as a WW1 fighter pilot he had won the coveted "Blue Max" and commanded the Red Baron's crack flying squadron, and as a war hero and leading politician, his massive powder blue 540 K Special Roadster was seen as a chariot of power in pre-WW2 Germany.

The exclusivity of the Special Roaster along with the remarkable provenance that such people add means every one has a storied past, which further adds to the legend and desirability and that's why they all sell for so much at auction.

The 1936 540 K Special Roadster at auction in Scottsdale

Elite auction houses do everything well, as would be expected given the profile of their buyer/seller clientele, and RM-Sotheby's is the leading elite auction house of the big three. The approximate 25 percent they retain from the sale of each car includes "white glove" everything, including employing copywriters and photographers to capture the story and character of each car. The extensive auction description for this car tells a wonderful tale and concludes: The 540 K Special Roadster is among the most instantly recognizable, valuable, and desirable of all automobiles built during the Classic Era, and acquiring one is an instant mark of discerning taste and prestige for any collector. It is, quite simply, the ultimate bragging right. Offered here is the opportunity to purchase not only a Special Roadster, but also one that may have been the last built and boasts a fully unique, owner-commissioned design, with features that elegantly bridge the gap between 1930s elegance and 1950s streamlining. It also offers the advantages of a five-speed overdrive transmission, matching numbers, a wonderful story, and an excellent restoration. It is, quite simply, a singular car.

So what will it sell for? That will be decided by the state of the market revealed in Scottsdale, with RM-Sothebys estimating $7,400,000 to $8,400,000 some 42 months after it last sold. Here are the precedents.

The 10 most valuable 540 K Special Roadsters

1 – 1936 540 K Special Roadster | $11,770,000

Sold: August, 2012, Monterey Car Week | Gooding & Co auction description

New Atlas writer Matt Kennedy has worked in the elite auction industry, and defines provenance as "the story you're going to tell your mates a thousand times." When it comes to great stories, the 540 K Special Roadster of Baroness Gisela von Krieger of Prussia is obviously worth at least a few million bucks on the auction block. Other than being owned by the beautiful Baroness, it's not that much more special than any other roadster on this list, but as the ultimate representation of the hedonistic lifestyle of society's elite, it has generated stories in the New York Times, Robb Report, Los Angeles Times, and Forbes magazine, not to mention a book.

No-one who can afford a genuine Special Roadster will keep it in anything less than perfect condition and that delicious provenance made all the difference when Gisela's Roadster crossed the auction block at Pebble Beach, elevating her 1936 540 K Special Roadster to a world record price for the model.

Among the very elite of international 1930s European society, the beautiful Baroness was named one of the ten most fashionable women in the world during the 1930s, led a very colorful lifestyle and kept the car stored untouched for three decades until her passing in 1989.

David Gooding of Gooding & Co saw the car still in storage when he was heading up Christie's automotive department, and recalls her driving maps and one elegant glove in the glove compartment, plus her lipstick-stained cigarette butts in the ashtray.

Esoteric Curiosa best encapsulated her lifestyle with this paragraph: Rich in both 'cash and looks', Baroness von Krieger's ethereal beauty, which was an ash-blond version combining the facial features of both Garbo and Dietrich, as well as her matchless elegance, bear credence to the account that one desperate admirer threw himself out of his plane over the English Channel when she refused to marry him. As a testament to her popularity amongst the male of the species, Gisela received virtually all of her important jewelry from her numerous admirers.

That jewelry alone fetched more than $3 million at auction two decades ago. Quite appropriately, Gooding & Co sold the car at that record price 14 years after David first saw it. The $11.77 million it fetched pushed it into the four most valuable cars in the world at the time, with the then world record being $16.4 million for a Ferrari 250 Testa Rossa.

2 - 1937 540 K Special Roadster | $9,900,000

Sold: January, 2016, Scottsdale, Arizona | RM-Sothebys auction description

This is the car first owned by Reginald Sinclaire, the heir of Henry Purdon Sinclaire, one of the founders of Corning Glass, and is one of the earliest known examples of the 540 K extant. Reginald would have paid New York importer Mitropa Motors around $14,000, about 40 percent more than the most expensive catalog-bodied Cadillac V-16.

3 - 1937 540 K Special Roadster | $9,680,000

Sold: August, 2011, Monterey Car Week | RM auction Description

Starting in Germany, this car has lived in Switzerland, Austria, Argentina, America, Australia, and for the last few decades has been in America.

4 - 1937 540 K Special Roadster | $8,106,150 (£3,905,000)

Sold: October 2007, London | RM auction description

In October 2007, Formula One supremo Bernie Ecclestone decided to clear out the shed because he wanted to buy more cars for his F1 car collection, so his high-door, long-tail Special Roadster had to go ... along with 13 Ferraris and a few other cars.

The car was delivered new to Sir John Chubb, of the famous lock company family. In the early fifties it was purchased by Edward Gaylord and was refurbished for him by Mercedes-Benz. In 1956 it was acquired by the noted American designer Brook Stevens, and was displayed in his museum in Wisconsin for some 30 years. At some point, the car was converted from its original UK right-hand drive specification to left drive configuration by the factory. In the mid-nineties it was given a professional "nut and bolt" restoration, after which it began winning numerous awards at shows and became part of the Ecclestone Collection in 1995. Although the restoration was effectively 20 years old at the time of the sale, it still fetched a handsome price nonetheless.

5 - 1939 540 K Special Roadster | $7,480,000

Sold: August, 2013, Monterey Car Week | RM auction description

This is the last time the car which will sell in Scottsdale on January 20, 2017 went to auction.

6 - 1935 500 K Special Roadster | $5,901,252 (€5,290,000)

Sold: September, 2016, Château de Chantilly | Bonhams auction description

This car has an even more interesting history than those above it on the list as it was "liberated" as war booty from Berlin in the aftermath of WW2 from Industrialist Hans Prym and no-one seems to know what happened to it until it appeared in America in the 1970s. It was sold at auction during the 2011 Monterey Car Week (see #9 on this list) and when the new owners displayed it at Retromobile in Germany in 2012, it was seized and became the subject of a legal dispute with Prym's descendants. The Prym family won, and this sale was the Prym family selling the car for a second time.

7 - 1939 540 K Special Roadster | $4,620,000

Sold: August, 2011, Monterey Car Week | RM auction description

This is the first time the car which will sell in Scottsdale on January 20, 2017 went to auction.

8 - 1934 500 K/540 K (factory upgrade) Special Roadster | $4,225,093 (€3,105,000)

Sold: July, 2014, Mercedes-Benz Museum Sale | Bonhams auction description

Yet another fantastic tale accompanies this car, with it being rediscovered in pieces in a barn in Poland, and eventually returned to its former glory. The car had been upgraded by the Mercedes-Benz factory to 540K spec prior to WW2 according to factory records, so it's a "real one" and to cap off the fairy tale, after it was restored, it was donated to Swedish Cancer and Alzheimer's Charities to provide funding for medical research.

9 - 1935 500 K Special Roadster | $3,767,500

Sold: August, 2011, Monterey Car Week | RM auction description

The previous auction sale of the car which appears as #6 on this list.

10 - 1937 540K Special Roadster | $3,630,000

Sold: January, 2002, Scottsdale, Arizona | RM press release

This is the car once owned by Hollywood mogul Jack Warner, and when it sold 15 years ago it set a new auction record for a Special Roadster. The history of the car is well documented by Paul Russell and Company, which did extensive work on it.

11 - 1937 540K Special Roadster by Mayfair | $2,530,000

Sold: August, 2007, Monterey Car Week | RM auction description

It was supposed to be a top 10, but we had to add this one in because it is one of the very few Mercedes-Benz Special Roadsters that wasn't bodied by the Mercedes-Benz factory's Sindelfingen works. This car is considered by many to be the seminal work of the Mayfair Carriage Co.

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