500 Usd
Impossible to answer without the serial number.
Need serial number to determine year of mfg. Look under the tang.
Totally depends on condition and grade (field, skeet, etc.) Your best bet is the Bluebook of Gun Values.
100-2000 usd
10-400 usd
Impossible to answer without a detailed description and the serial number.
100-599 USD or so
Couple of thousand USD
Made in 1987. Value could be from 500-multiple thousands. You don't describe what grade, if it was made and assembled in Belgium, made in Belgium and assembled in Portugal, describe the condition, accessories, box, papers, etc..
Requires professional appraisal
Impossible to value with only a serial number.
Impossible to value with only the serial number.