You realize Cycling Tom that Jessy 87 wrote that on July 11th, so the tomorrow that he mentioned in his post was July 12, this is September 3rd, so he has either bought the bike or not.
Just in case he's still reading this on his email, and he bought the bike, I would recommend he buy a second one to use as parts when he can't find a part anywhere else. Plus if he decides to tackle an engine rebuild by himself, and he's never done one before he can use the spare engine to practice on before doing the main engine.
The only weak spots I've ever heard of those bikes were the carbs, and since they used 4 carbs you have to know how to adjust multi carb setups. The other was the electrical, including everything electrical related, especially checking for corrosion at the connections.
Other than that any other weak spots are typical with ANY used motorcycle, checking stuff like the chain and sprocket for wear or damage; the cam chains to make sure they're adjusted correctly; checking the suspension, etc.
Other than that stuff you have your usual maintenance items that should be checked and replaced as needed. like oil change with filter, brake pads, cables, spark plugs, battery, and gaskets.
Not seeing the bike I have no idea what shape the bike is in, was it totally restored, was it average used condition, we don't know, but for the price I think it may have needed some work since really good condition bikes go for 9 grand with an average condition price of 5 grand, so that leaves me to believe that it needs a lot of work.