Looks like the valve check intervals are 7500 miles (here in the U.S). Are the valves generally in spec with those kind of miles or do they typically need adjustment?
That almost always depends on how the bike was ridden
It wouldn't hurt to ask the owner about its riding history. Did he/she ride tracks days or local club races? Was it just a weekend entertainment tool? Was just ridden down the highway to the local starbucks for everyone to gawk at? Get a feel for how the bike was ridden and also ask for proof of service history.