I just bought a 1987 190 2.5 DT last spring. 180,000 miles.
It needed work. mostly small stuff. $2,600. +tax.
I discovered that the climate control module had fried because the aux coolant pump had siezed. $400 in parts later have great heat. But checking to see if the aux fans worked found they did not. Full of gravel/sand. just try to spin them to see if yours are too. I was able to remove them and take them apart to blow out the crud in the motors. One just needed ist bearings cleaned and repacked...the other needed brushes. $40 and a few hours later I had my aux fans back. Replacement cost would have been about 8 time that...without labor charges.
The dealer (not MBZ) replaced the tranny...(top gear was gone)..as part of the deal.
I still have to weld in new metal around the jack points..they all seem to rust badly in that area in the northern states. And I had to slip a cover on the cracked dash. Very easy and looks like new.
I got a bargain! As of now I have about $3,200 in it! What a great little road car! Very smooth and nimble on the road and unlike many diesel vehicles..quick!
Dana