You know, it is kind of funny how most have replied in favor of the Owner and the truck instead of JM603, who doesn't like deals? I mean, would you guys really offer market value on a truck that no matter how well it looks and works? Its not a new truck anymore no matter how we look at it. Heck, even on new trucks people haggle with the price, nobody walks into a Dealer and just says "I would take it for the sticker price..." Or maybe there are people that do... Now, sounds to me like the owner is not really in need to sell it, so maybe he knows and wants the truck to go to someone that would use it? If it was me, I would just be insisting on Owner to name its price and go from there to see if negotiation can work, probably where we both feel its fair.
The owner by saying "make me an offer", makes me think that he probably has a pretty good idea of what the truck is worth, and maybe thinks prospective buyer is uninformed thus yielding him a bigger number than what he knows the truck is valued at...