That 1994 E420 with 40k for $15,000 looks like a great deal at first glance. What is the condition of the paint and interior? I would check closely for body work and repainted areas. Does the owner have service records for the car? What's the history? Has it been sitting for an extended period or just driven sparingly over its lifetime? If this car has sat for an extended period there will probably be issues with deteriorated soft parts ... gaskets and seals. At any rate the V8 will be more expensive to maintain and fuel than the straight 6's that you're used to. Also, more cramped to work on if you do your own mechanical work. Before you buy have a mechanic experienced with MB go over the car completely so that you know exactly what needs immediate attention and what to expect in the long term.

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Fred Hoelzle