Stop in for a cup of coffee

Not a lot unfortunately... did some quick online looking. $300 - $600 (mint) A lot of recommendations to not fire them with modern 12 ga shells. Not sure what that's about.
Hmm probably because modern pressures are higher. That said, I can’t imagine some low brass target rounds will hurt it much. High powered slugs or high brass loads, that I could see. That said, it’s more of a trophy at this point. With all the modern 12s I have, it’s not worth risking.
Some things are just cool to have.

I have a car in the garage that has infinite personal value but little market value.

Yup, I'd kick some.serious %@$ to get any of my grandfather's old firearms. They're gone forever

oh I’ll never sell it. I just want to make sure I have it declared right on my insurance should something happen to it. Same with the other old 12 gauge I got from the estate auction (which pissed off extended family hehe). I over paid but oh well. I made it up on the reproduction Marlin 1895 45-70 cattleman’s special. Number 3 serial number.