Your shotgun was mfg in 1981. Used gun values are driven by several things. Condition of the firearm, model, chokes, with or without paperwork? Go to a used gun site like gunbroker.com and compare.
Browning Citori 12 gage over and under & a Browning Goldtrigger Light Twelve: How much are they worth?
50-1000 usd
No way to answer without a detailed description.
What is the value of a 12 gauge Browning shotgun serial J68824?
Shotgun made by Browning.
50-500 usd
50-500 uSD
50-650 usd
A bolt action shotgun in 12 gauge.
100-1000 usd
300 or so
Impossible to answer without a detalied description of all markings and features.