FOUR McIntosh monoblocks? I've seen those go for that much EACH in pristine condition ...
I'd be more worried about the tubes ... but with four units, I'm sure you could come up with a killer set or two. Given my druthers, I'd try for a matched set of original tubes. If they all light, that's a good start. I'd also pop the covers and see what they look like inside, but they're fairly well sealed so I expect the innards are decent. Yes, they do have obvious cosmetic issues, but looks ain't everything. You may get away with just doing a pin cleaning on the tube sockets, controls, connectors ... the usual. You can also do some spiff and polish on the cases and end up with a decent "custom" brushed finish, or just strip them and refinish - lucky you, they're not chrome, and you should be able to recreate the original hammertone with a bit of patience.
One word of caution ... they've probably been sitting for a while and will need to be brought up to power slowly. Ideally, you'd have a variac to build up to operating voltage and allow the caps to reform, but ... rather than get too anal about it, call ahead and have the seller just plug them and let them idle for a couple hours first. If the house ain't burnin' when you get there ... they'll probably be ok. <G> Do a test listen at low then moderate volume, and if you can't resist, crank them up to decent volume but only for a short time. If he objects to a test run or doesn't have the equipment to do it, flip a coin or move on.
I'd be tempted to offer $400 for a pair - AFTER a test listen. Steer yourself towards audio quality instead of looks. If they sound good, maybe bump up to $500 if he objects. If they don't fire, they'd still be a nice project at a reduced price. In any case, if you've got the bux to make an offer, leave your name and number in case yours ends up being the best offer.
Wouldn't be surprised to see a couple PMs coming your way if you decide against them. I'd be interested if I didn't have an MC2205 idling away in the other room ... <G>