I've had my 12 gauge 30 inch barrel, 3" chamber, fixed choke which I believe to be modified and full, I can check this later and send photos if it will help.
It's a 1981 Citori over and under and decided to sell it to one of my friends that's wanted it for a while. it's in pretty good condition with some mild wear for being a 40-year-old gun there is some small pitting in the top barrel about a quarter of the way down on the inside. Trying to come up with a fair value for him, I do see $800 to $900 it seems like on this gun but I can tell it varies based on chokes and condition.

It seems like about a $700 to $750 gun to me.

$800 tops.

I recently bought a nearly perfect ‘81 Citori like that with 28“ barrels for about a grand. If it had any rust I wouldn’t have paid over $700, if anything.

Bought a 1983 Citori with 30" barrels, 3" chamber fixed mod/full chokes in excellent condition with no pitting and no rust 6 months ago for $735 including shipping and transfer fees. I think the gun was listed at $680.