I'm going to be a little contrary.
Be honest on the tires, and state that the price is accordingly adjusted to allow for personal choice, etc.
As far as the chain and sprockets, I'd replace them. For me it speaks more to good routine maintenance. If I'm looking at a bike that needs tires, and a chain and sprockets, I'm wondering "What else does it need?" and "If the guy is too cheap to do the basic stuff, did he ever check valves, change the oil, check the screens, flush coolant?"
I think the tires are easily explainable, but the basic maintenance is not.
DRZ440E, KLX440R, DRZ250, KTM 950S Adv, F650GS, & F650GS Dakar