Value is too difficult to be accurate without seeing the gun. Condition which includes the amount of original finish and original configuration will determine value. Auto 5's with recoil pads (other than Mag 12's) poly-chokes and compensators will reduce value. Recommend taking it to a gun shop for appraisal.
100-400 USD
It was made in 1968
Browning.
Try www.Gunbroker.com. They are no longer produced.
Impossible to answer without a detalied description of all features and markings.
@ 400 USD
75-575 usd
The A5 20 ga. was made in two models: Light 20, and Magnum 20. The Light twenty, sometimes just reffered to as a "Browning Twenty" was made from 1958-1976 in Belgium. The receivers are marked "Light Twenty" The Magnum version has a 3" chamber and was made in Belgium from 1967-1976. The receiver on this gun will say "Magnum Twenty" Other differences are the weight of the models
A few hundred to a few thousand.
Depending on the exact configuration and condition, a few hundred to multiple thousands of USD.
Weight.
100-600 usd