Dieter,
I have not seen this, and a "concours condition" 190SL at $35,000 is surely a hoax, a mistake or similar.
Note to the wise: this site that Dieter listed,
www.classiccars.co.uk is specifically the kind of site to be wary of. If you cannot readily obtain a phone number, a physical address, and a name or two--and double check those facts against other things, it's really time to just walk away. Any honest reputable person maintaining such a site would make that information available, if not: they do NOT want to be found, so don't try... There are plenty of other honest, reputable dealers and similar that WILL talk to you, will provide an address and phone number and that's one way to separate the wheat from the chaff.
BTW, the seller (or broker I should say) of this POS 190SL unrestorable rust bucket, is quite easily traced. He's a lawyer with this car brokerage hobby out of Daytona Beach. Easy to find two physical addresses for him. Doesn't make this 190SL any better but at least you are not dealing with an untraceable ghost!