No nothing out of the ordinary. You will want to check and insure the rear linkage has been properly serviced and the bearings are still in good condition. Raise the rear end off the ground, have someone support the bike and twist the swing arm back and forth. There shouldn't be any play. If the owner is game remove one of the linkage nuts, remove the seal and insure the bearing is lubricated. If they are bad don't walk away from the bike just insure you work replacement parts into your price.
Talk to the owner about the new top end particularly about how he removed the cylinder. You want to make sure he knew the main kips shaft used a reverse thread nut and that he supported the shaft when removing it. Failure to do so could break the bottom of the shaft dropping pieces into the transmission. It wouldn't be a crazy idea just to replace the shaft on a used bike just in case, as they are fairly cheap.
David