Don't be too quick to make your decision based on 'no rust". The 940's have a reputation for staying rust free significantly longer than ther earlier 700s and (understatment) the 200s. As evidence, I just bought a 93 940Turbo wagon with 153K on eBay frim a dealer in Rochester, NY, which has an average snowfall, I believe, over 200"/year. The car was clean, save a small area on the rear axle housing. Of course consider rust, but concentrate on the engine/drivetrain, suspension, and, in my experience, the interior. The condition if the interior tells you something about the previous owners regard for his/her brick and how it was serviced. My $.02 is there are better cars available than this rough to average one.

Jim Weiss
83 245T (no rust, I'm still baffled}, 90 760TI (no rust, but its from Atlanta)
93 940TI wagon (first winter in Chicago, so, we'll see)