Perhaps rules should include emphasis that the person making an offer is OBLIGATED to follow through, and in timely manner, upon accepted offer (to discourage flakeyness and STS, or second-thought-syndrome).
Don’t offer, unless you’re ready to pay !
Perhaps an emphasis that seller is similarly OBLIGATED to follow through, even if a higher offer comes through subsequently, or behind the scenes, or “sorry dude, the dog ate my reflector.”
Honorable behavior is the norm here on the Cabe, but it never hurts to spell it out for those challenged in this regard.