There used to be a guy who came around to our local supermarket...he represented at least one Canadian pharmacy. He would take the orders, send them in and deliver the meds when they came in. I asked at the market if he was still around. No. He was caught and told to cease and desist, or he’d wind up in jail.
Never hold the meds.
Never carry inventory.
Act as an order taker, only.
Use the Canadian and U.S. Postal Service.
Not saying it is perfectly legal, or legal at all, I am only saying that, so far, the government tends to leave you alone if you operate this way.