This cannot be answered without a detailed description of the shotguns condition.
Browning Arms
You will need to supply the serial numbers to your shotguns to get the age of your browning shotguns correctly.
Besides a number of books published on Browning, and some of the gun collector forums (google Browning collectors) you might start with Browning. They have a website, and are still in business making very nice rifles, shotguns, and pistols.
The browning auto-5 shotguns are going for anywhere from 375-650 dollars depending on condition.
They will have "Made in Japan" on them somewhere. Value will depend on exact configuration and condition.
Contact Browning.
www.browning.com
If you have the money.....
All Browning B-2000 shotguns were Belgium manufacture but assembled in Portugal.
It will depend on the specific model and its condition. A quick look at the GunsAmerica.com site shows Browning Sweet 16 shotguns listed for anywhere from $650 to $2500.
Yes.All Browning shotguns made prior to the year 1976 were Belgium made shotguns.