yo bro ...
Probably the biggest problem will be getting spares - eg mirrors, instruments, suspension. Tyres were hard to get until Michelin made some more recently. I couldn't get a new second gear a few years ago (but I got the dogs re-machined, and paid the engineer with some artwork - that's the kind of bike they are - real engineers appreciate them). Many bikes more than a few years old have parts-supply problems. Having a Paso makes the problems worthwhile. They are special motorcycles - very deep. People are selling parts from old ones all the time.
If it doesn't run well low down, maybe it's still got the origingal Weber carb, which can be fixed by fitting a fuel pressure regulator (they're not expensive). If it doesn't start easilly, maybe the electrics need fixing up. If it doesn't run well when it's cold, maybe the valves need adjusting.
Get it.