Hi Paul and welcome to Ninjette!
I believe you have FI model in your area? Which alleviates a TONNE of possible problems relating to fuel petcock and carbs when sitting for more than 3-months. Should check following:
- compression/leakdown test to determine condition of engine innards
- inspect interior of tank with powerful torche and look for rust
- service records, look for valve-clearance inspection and adjustment, should be done every 7500-miles
- tyres, not too old and no cracks in sidewall allowed
- brakes, discs are smooth and pads not worn. Firm lever & pedal squeeze
- steering head bearings, shouldn’t have freepoay. Test for wobbling clunks when pushing forwards and backwards and applying front brake
- wheel-bearings, grab top of wheel at tyre and shove sideways back & forth. Should have bike securely up on stands when doing this to remove weight from bearings
These bikes are pretty bulletproof. Takes lots of abuse without too many issues