I forget the gentleman's name, but a fellow here had 3 different 400E/E420's over the years and was a travelling salesman. The fewest miles he put on one example was 275k. The other 2 topped 300k, and even sold one to a friend :O.
This was just another data point that conviced me of the M119 (and W124 chassis for that matter) longeval qualities
. You'll have to pry the steering wheel from my cold, dead hands to ge ahold of mine.
I payed $21k but that was for a previously Starmarked car with very low miles - I've seen beaters go for half that. Tracy offers some sage advice. Could be it needs a ton of stuff, it's just had a ton of stuff done (and will be trouble-free for some time), or somewhere in between. Those 'inbetween' things can add up though: timing chain/valve work, evap core, etc....get it thoroughly inspected.
Regards,
- Ryan