People think differently. When I buy used scooter, I look for the signs about how keen the owner has been about the scooter. One thing can be, that if he has both of those manuals, he is probably more keen than the average about to keep his scooter in top condition. Probably. When small things are counted together, its a sign for me, whether there is a chance to make an offer, or go to look for another, perhaps the one that has more miles ahead than back.
Takes some time and work, and usually pays back.