When I was 15 I road my bicycle to downtown Waco and bought a 20 gauge (may have been a 410) single barrel shotgun (for, I think about $20) from a pawn shop on Austin Avenue! No big deal waaay back then.
I had a new bolt action 20 gauge with a detachable magazine and the screw in choke. $60 I think. Traded it in for my 30-06 which I still have.
At some point I bought another bolt action 20 guage with a detached magazine, but no screw in choke. Still have that one.