This final year W211 generation E-Class checks a lot of boxes with low-ish miles (especially for a diesel), a long history of dealer service, and no accident history. I like the diesel variants because they return excellent fuel economy (26 mpg combined) and have gobs of low-end torque (400 ft-lbs at 1600 rpm). While the OM642 engine isn’t quite as bulletproof as Benz’s earlier iron block oil burners, it should have at least another 100k miles in it with continued regular service and maintenance.
Offered on craigslist HERE by a private seller in northern Washington State for $9200, which is a fair price for a nice example (and still probably some room for negotiation).
For less than ten grand, it’s a super nice, comfortable, and classy ride.