No problem - it probably varies a lot by regions guys ....
I'm a used gun shop junkie .......and I try and get to my local shops 5 or 6 times a month just to see what's coming and going ......and just last month, a young fella came into a local shop with probably 2 dozen shotguns from his dad's estate ( nothing really special ) but there were at least 3 model 12's ...and most of them were not in great shape ....but I heard the owner tell the kid, he didn't really want the model 12's ...he had so many ....(and I think they were 20ga and 16ga ) ..
At least around here ....these older fixed choke guns / especially if they're choked Full ...just aren't very versatile for general shotgunning ....and they don't sell well. In my buddy's shop / most of us old guys have all the pump guns we want ... maybe more than we want .... and the guys under 30 yrs old for the most part ...want synthetic stocks, short barrels, etc ... / and buying a used gun and putting a new barrel on it will often cost more than the big box stores are selling the Mossberg and Rem 870's for new in all the tactical configurations ....
Its not just the older model 12's that he has trouble selling - its 870's, Browning BPS, etc if they've been used for hunting, scratched up a little and have fixed chokes ( unless it's Modified, or Imp Cyclinder ) ...they're just hard to sell. Now the exception is a gun that comes in really clean / that a collector might want ....is a little different. If its been a safe queen / he will often buy it / or if it's a .410 or a 28ga that will make a difference as well.
But in my area / the days of bird hunting and waterfowling are pretty much over / unless you want to travel at least 4 hours or more one way .....so there are a lof of older "field" shotguns on the market with Fixed Full chokes and there just doesn't seem to be any buyers for them ....