I don’t want to be “that guy” but why not reach out to the guy who offered you $1000. I know it’s a lowball offer but you are selling used equipment. Most likely then not … without warranty correct?
Sometimes as a potential 2nd owner we have a number (budget) in our head on how much we are willing to spend (risk) on purchase knowing we might be out luck in a day, a month, or maybe get luck never have an issue … either way it’s a roll of the dice.
Anyways … good luck with the sale.