I did it in 1979 as a 16 year old. It was a local department store. I don't recall the process, exactly. But I'm pretty sure I gave them the cash, and they gave me the shotgun with the only "paperwork" being a receipt.+ Before 1968, you could walk in a hardware store, buy a gun and walk out without any paperwork done.
There were millions of guns sold that way...
I regularly bought ammo at the local Western Auto hardware store.
I posted about that shotgun in a thread: https://www.floridaconcealedcarry.c...ught-my-very-first-firearm-so-excited.139633/