I have some preban 20 round mags listed for sale. I would prefer to sell them to someone in a ban state. I have someone interested who is not in a ban state. If they give me the "I'll take them" can I ask them wait a week until I see if someone who needs them steps up without getting called on the carpet for an "I called them first"?
You can sell to whomever you want, just as long as whoever you tell "it's yours" you follow through with them.
There's a few people out there that
buy poach them for the sole purpose of reselling them to ban state residents for a profit.