Thank you for the advice, you confirmed my mechanic’s advises. I am not a mechanic and can not DIY.
The seller is asking $17K for the 97 S320, 67K miles + 8 months of Starmark.
KBB is $15K private party; for other cars I have found KBB to be 20% over market price; don’t know if that applies to MB. Current owner extended Starmark for 2 years; could I extend for another 2 years? I like the S320 – I am 6’4” and need a car with space that I enjoy driving; like to drive the family around in a roomy and safe car on weekends and trips. I will look into the E320.

throw him a low ball offer and if he doesn't take, no worries~

I just paid $14,500 for a 1999 S320 with 99K. Not sure of the Starmark status as the car was a Starmark Certified Preowned when the previous owner bought it.

I would not really be "afraid" of these cars. I do some simple DIY work myself and have an independant mechanic that does my big jobs. If you locate a good independant you can save a lot of money. In my opinion the w-140 is the most comfortable and best built Mercedes ever made. With this car you do get what you pay for.

If you really need help making a decision get the dealer to let you take the car for an afternoon. Go on a long drive somewhere and you will be amazed how refreshed and relaxed you are when you arrive. In my opinion you can't really attach a dollar figure to that.

As for the E class I have driven several from several years. Honestly I would rather drive my 82 300SD than any E-class.