I too would be wary of buying a Pro's camera. Sure they are built like tanks, but they are put through the motions almost 24/7; after all, that's what the Pro's buy them for - work, not admiration.
I assisted a photographed for approximately 9 years - and in that time, about the only maintenance he had done on the cameras we used was to have them cleaned (and then I could count on 1 hand the number of times that was done). We worked these to death - 1000s of exposures and they were used hard (not treated poorly, just really worked).
He put an F5 up for sale which hadn't seen an awful lot of work, and he made sure to have it serviced first - that was a bargain for the lucky buyer, as he moved to digital not long after purchasing. It got a fair amount of work, but nothing like his F4 and earlier bodies.
The best bargain I ever landed was from an older gentleman who decided to move to digital - traded in all his lovely EOS gear at a local camera store. I think from memory he had only had it 18 months at most. 3 weeks after trading "up" he wanted to trade back - I got a nice body and flash out of it - he on the other hand would have lost out badly. . . .