In the case of a personal meeting, choose crowded places like a cafe or a square, and receive payment at the bank by checking the money for authenticity
Sure, Path to the Peak (Chilling Reign) can shut it down, but you can always run Chaotic Swell (Cosmic Eclipse), Marshadow (Unbroken Bonds), or even Pumpkaboo (Evolving Skies) to get rid of it
When GameStop started doing it, it was without providing the staff with the necessary training and expertise, and naturally saw them paying woefully low prices, and of course without any of the individual stores having any independence over how it was carried out
It is also worth noting that no matter how much you compress, some air will remain
Likewise, Lightstall Inquisitor looks pretty interesting, Ill admit, but beyond Giada decks, it doesnt have a home in Commander