I just bought a 1993 190E and I love it! That said, I just replaced the head gasket as well! Luckily I could do it myself, and save $2000! But check everything out, and you should be alright. Check out this link, I'm a member there and you can find just about anything 190e related
I personally think that $6999 is way too much for this car. I bought a limited edition that was the only 190E that came with leather and a couple of other things for $5000, so maybe you can negotiate with the guy. Good luck!