Keep everything on the up and up. Any and all advice received here should be followed on your own accord after being thoroughly fact checked. Any and all things discussed on this forum do not suffice as legal advice, all parties are encouraged to contact their local AHJ to stay compliant with all federal, state and local ordinances.
I would like to offer a word of warning about this seller. He flaked out on me and there is a good chance he will do it to you as well. I Spoke with him on Sunday about looking to buy one of the guns he has listed before we drove the hour it takes to get to Grand Junction. He said he would be available as long as it was after 12 pm. We arrived at 12:30 pm and he had stopped communicating and never responded again. Unfortunately, I hoped he was just away from his phone but 5 hours later we still had not heard back so we went home. Wasted the better part of the day just for him to flake out. 2 days later he still hasn't had the common decency to respond any text messages.