I wouldn't give much more than 4k for it... depending on what's been replaced under the hood. It seems like once you buy it everything starts to crap out on you and now you're into 10k total with the car and you've still got a rusty benz. That rust isn't bad, my car has rust, not as bad as the one you're looking into but still what that car has is tolerable and won't be a problem for years.
But I'd look for another. There's LOTS of 'em out there!
(like my new avatar?)
