Impossible to answer without a detailed description of all markings, finish, barrel legth, action type, condition, accessories, box, papers, etc..
your browning auto-5 lightweight 20 ga was made in 1963.As to value they are going between 450-650 dollars depending on condition.
50-500 usd
100-1000 USD
No
100-1000 usd
50-500 usd
100-1000 depending on specifics
100-10000 USD or more depending on specifics
50-500 USD range
200-1200 usd
100-2000 USD or more depending on specifics
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