I wouldn't let the car go ... if you can afford to do so, your best bet would be to buy a newer, more maintenance-free car but keep your MB as a strictly hobby car. That way you can repair/restore it as time and money allows. Of course, this would require some means and a place to store the car, and that may not be an option for everyone. But personally, I'd never advise someone to get rid of a car they love. You can't get it back (well, not usually). To me -- and admittedly I'm in a fairly fortunate position financially -- enough is never enough. Maybe I'll have to put it on the shelf at some point, but I don't think I could ever just give it up completely.

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1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)