Scott Featherman in Sports Car Market profiled these a few years ago..

Here are couple of his remarks....

"It takes a true specialist, with first hand knowledge and experience, to service, repair or restore these machines. For example, the hydraulic system requires a lightweight special purpose oil. MB Part #100 890 00 11. While this looks like typical ATF fluid, if ATF fluid is innocently dumped in the hydraulic reservoir-the system that powers the seats, windows, ventilation flaps, sunroof, trunk lid, shocks and on the early models, the door assists, you have just committed a $30,000 faux pas. Typical rebuild costs: Brake system overhaul, $25,000; front or rear axle assemblies $12,000 each plus $6,000 for the rest of the air suspension system, driveshaft $7,000, Fully restoring a 600, if you begin with a complete decent $20,000 builder, will set you back at least $150,000


"Obviously if you must have a 600, you are better off spending at least $70,000 for a good car with 40,000-50,000 miles that has been maintained, with a thick folder full of documentation. Top condition SWB 600s will bring well over $100k from savvy buyers who are aware of what it takes to make one right..."

"If the car runs out OK, and the owner drives it for a year and then sells it without doing anything, he will probably get his money back and have had a good time. But if he comes out one morning and notices the car has adapted a kneeling position at one corner due to the collapse of the air suspension, he should be aware the good times have ended and the fiscal future is bleak."

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)