I agree on the body work,gone are the days of "restoring" cars just because they were old,buyers today look for originality over new upholstery.Wear is part of a cars Character.
Mechanial things on a 600 are seriously expensive,e.g pistons ...$1100 each. interior "comfort" circuit hydrualic switches...$2000 each ,and they do break because the diecast material deteriorates over time,the emergency kitset for the trunk has $23,000 worth of parts in it,such as a spare ram for the trunk lid.
Disc pads are $1200 for a set ,although another friend in South Africa has managed to get sets made for $80 a set.( if you need a spare set ,send me a PM and i'll pass his address etc on),then there is the air suspenion...while not as complex as others will have you believe the valves are rebuildable at $300 each ,the bags are $180 each,all this can be avoideed with a bit of driving,bags etc will last over 30 years on a regularly used car.
The auto trans will start leaking if the car is'nt used enough and handbrakes stick on...
So if you buy this car count on paying a knowledgable specialist at least $30,000 to make it roadworthy.
But read the feedback before committing yourself