Please identify what kind of gun this is and ask the question again
Impossible to answer without a detailed description of all markings, finish, condition, box, papers, accessories, etc..
You need to bo to Browning.com since you didn't provide the model and use the sn function.
Without a better description; 10-1000 USD
100-10000 USD depending on EXACTLY what you have, its condition and history.
Impossible to answer without a detailed description of all features, markings and condition.
Fabrique Nationale (the name of the company) arms of war, Herstal, Belguim (place of manufacture. Brownings patent filed.
FN made hundreds of different caliber rifles, pistols & shotguns both military & civilian. Need more info. Be specific.
Most FN production records from WW 2 and earlier were lost during the war.
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. Recommend taking it to a gun shop for appraisal.
Depending on condtion 200-400 USD how can a browning in almost perfect condition ,1925 model with only a 4 diget ser.no only be worth 400.00.
La Guerre was created in 1970.