Are you talking about a Browning Model 12 reproduction, or a Browning BPS in 20 gauge? In either case, you are looking at 250-700 depending on conditon, etc.
Between 1200 and 1750 US
29 years old; 100-2000 USD
No such model number ever used by Browning.
Can't be answered without a detailed description of action, stock, barrels, markings, etc..
Not a valid Browning serial number.
500 or so
100-1000 USD depending on specifics
£900 - £1000 in mint condition
50-1000 usd
according to Browning Service and a local gunsmith - YES
The value of a 1926 Belgium Browning A-5 12 gauge with custom stock is actually dependent upon a number of things. Most important would be the condition of the firearm.
100-400 USD