Greg, I would only buy something like that if you are a collector or it has special meaning to you from your days growing up. My avitar bike is a red 1966 S90 and is quite special to me as one like it was my first real motorcycle at age 11. I'd had a minibike earlier, but this thing had a clutch and gears - man I was on "cloud 9". Even that said, riding it today is a joke. I'm 240 and my knees hit my hands when the bars are turned and it ain't nearly as fast and powerful as my imagination and memories thought it was. You'll never ride it more than to circulate the oil once in a while.
If you want it, I think it's a great price - just be sure you know why you're buying it.
Regards,
Gordon