I'd like to chime in but everything's been said. My only challenge is that the AC in my 91 300SE is as cold as I can expect it to be.
While you're checking for evidence of accidents, make sure all the body panels have the correct VIN tag. There should be a tag on each front fender (near the firewall), each door (near the hinges), trunk lid (forward edge), and possibly on the bumpers too. There might be more, but these are the ones I remember.
Expect to need a head gasket in the next 20-30,000 miles. If you need one, then it won't be a suprise. If you don't, lucky you.