no one has managed to actually wear out a oil head yet. some are over 500k
You will be replacing some parts along the way, but with good care you will never wear out the engine or the transmission or final drive, but you will need some rebuilding and repair along the way. and some bearings will need attention. It is all in the hall of wisdom.
See how many miles on the clutch and slave. Make sure the ABS works. Plan to upgrade the cam chain tensioner. Actual price should be less than 4K unless you have a new clutch and plates, new slave, new pivot bearings, maybe a big ball bearing in the final drive and rebuilt drive shaft, and recently rebuilt shocks. even then, price no where near 8K.