Looks pretty mint to be honest, and i couldn't believe the price either considering no rust and the low mileage!
I'd be a bit weary about the mileage, seems genuine and as you say seemed a nice guy, but just make sure it is genuine.
Coolant could just need changing, it's common for the expansion tank to get stained a rusty colour. Obviously, rust isn't really a good thing, and it can start to clog up your coolant pipes. Give them a squeeze in the bay to see if they feel crunchy or not. If they're crunchy then there will be a build up of rust in there so you'll need an anti-rust additive (not sure if coolant has this in), and the coolant system will need flushing out.
If the fans just don't work then thats just going to be electrical. Not a major problem to worry about and i shouldn't imagine it'd be hard to fix.
Clutches can be heavy in valvers, depending on what clutch is fitted. My valver has an insanely heavy clutch when i first got it, but it was a racing clutch so that was why.
If it's just a standard clutch then check the routing of the clutch cable through the bay. I'm sure some peeps on here can tell you where it's supposed to be routed, as if routed incorrectly it can make it heavy. I now have a standard clutch and i wouldn't say the clutch pedal is heavy anymore.
It's not unusual for valver engines to burn oil, mine does, but i know the engine is sound. I think it's just the piston rings being worn over time (correct me if i'm wrong). I have to top my valver oil up every few months. The harder i drive it, the more it burns.
Shouldn't really use coolant unless there's a leak or the headgasket needs changing. Check when this was last done, if at all.
Since my headgasket was replaced mine hasn't used any coolant whatsoever, and that was a good 8 months ago.
I say go for it, looks like a mint car, with a few minor issues to sort. Just make sure everything is genuine first!
