Posted By:
boxingcardmanA lawyer would say that as long as there is no misrepresentation involved and the seller is legally competent to contract, the fact that the seller doesn't know the value of what he's selling is irrelevant. If he understands he is contracting to sell a baseball card to you for a price you are paying, that should be the end of the story. Doesn't stop people from being sore losers and suing but doesn't mean they are right.
As far as what I would do, sitting here today pondering your hypothetical I guess as long as there's nothing unlawful involved in the transaction I would pay whatever I could get it for and be fine with the deal.
Sic Gorgiamus Allos Subjectatos Nunc