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-John Olson, Editor, SL MARKET LETTER Return to the Sample Articles Index 
(Source: SL Market Letter #237)
All manufacturers make plenty of B & D, less of A, and still less of C. "D" are cars that are literally unsafe, or too expensive to repair. Mercedes-Benz hasn't built anything obviously unsafe in our memory, though deteriorated engines & body wear or rust eventually create enough pollution or danger to go beyond the economics of rebuilding (vs. replacing). The most expendable models of all marques are the most common and successful (ironically). Often they are sedans. Some SLs are borderline.
EXAMPLE D-1 Sedans & junior models of every marque: Unless a car hits a home run in styling, performance or innovation, it will only become valued if it has 2,300 miles on it when it is 40 years old (or looks that way). Why be custodian to the mundane when it takes little more work to tend a masterpiece?
EXAMPLE D-2 (Mercedes) 280E, 300D, early 190E, 450SE to 560SEL with bad motors & rust: After dutiful years in group B, they depreciate below repair costs; it is time to cut bait & replace with healthy clones.
EXAMPLE D-3: Tired 450SLs: Even our namesake SLs can get caught in this circumstance. Rough examples should go begging at $6,000 because $10,000 won't fix them & excellent examples are available for $15,000.
At the other extreme are the great cars that everybody senses are "home runs". This is a little tricky, as the most prized collector cars today were rarely box office hits. Some certified Classic & Milestones cars were poor sellers either because of the economy or what seemed at the time an inordinately high original price.
300SL, S, Sc and 600: These were too expensive to sell in quantity when new, but it's clear from the Who's Who that bought them that they were revered from day one. Today their continued profoundness make them mechanical treasures that often escape all but ceremonial duty. Their status brings the ultimate challenge... immortality.
EXAMPLE A-2 Mid-1950s Corvette/ Thunderbird/Jaguar: These cars too are certified Milestones, worthy of being saved for future centuries as "home runs" of their respective marques. Uneven engineering & ergomatics however hinder Category B & C.
EXAMPLE A-3 Ultra-low mile cars of any type whatsoever: These cars are profound because of perfect preservation after creation, independent of their aesthetics or brilliant engineering. We remember judging a '62 Rambler Classic, 4 dr. Best of Show a few years ago, on a field with Duesenbergs & 300SLs. A 100 point original. There was shock, but no one questioned the results. Hopefully that Rambler will live for centuries. The ultimate catch would be a car that fits both Example A-1 and A-3.
Our favorite category is C, because Mercedes-Benz does so well in it. While not advocating that you drive a Milestone car for work daily, some autos are significant enough that they will be museum & restoration candidates even if used extensively beforehand. When one of these cars has very low mileage, it deserves to be retrieved from the real world, but the more common scene for future Milestone cars is normal mileage accumulation and a mid-life crisis during the years before they are properly revered. Since most are not low mileage oddities, they can provide distinctive daily transportation in their second & third decade of life until their era's nostalgia takes off. At that point a major restoration (by you or a future owner) will negate the relevance of past mileage. The true mileage of a totally restored car is irrelevant: only the quality of the restoration matters.
EXAMPLE C-1 5.0 liter SLC: only 2,756 were built: Even with 300,000 miles, they still possess their eliteness, the top of the line, incredible performers,and getting rarer each year. That can't be said for a 300,000 miles 450SLC.
EXAMPLE C-2 111 Body Convertibles: The world loves convertibles, and by and large loves Mercedes-Benz too. It's hard to make a mistake with any older 4/5passenger M-B convertible; they are beautiful, rarer than most SLs, and desirable enough to be used and rebuild time after time.
EXAMPLE C-3 6.3, 6.9, 190E 2.3-16, 500E, C36 These “banker's hotrods” will always be on the lists of most significant Mercedes-Benz for their respective decades. Even the oldest of the lot, the 6.3, is far from primitive. 50 and 100 years in the future they will still be giving their collector owners refined, air conditioned thrills.
Many collectible cars are "niche" cars. Many are also top-of-the-line models. Low production models & convertibles are the safest choices. Famous original owners, rare accessories, and authenticated prototypes are added insurance of "liquidity" (as distinguished from inflated prices) at resale time. When the Mercedes Museum archivists can verify M-B's hand in such oddities, save the proof!