It is worth about $125 in excellent shape on down to about $40 in poor shape. Unfortunately they built so many of these things that their is little or no collector's interest in them.
28 gauge with single barrel How do you find its age and value?
The value of a Topper model 158 12 gauge would depend on a couple different things. The main thing to consider would be the condition.
1901 single barrel shotgun, washingtion
About $70, depending on condition.
Under $100.
$75
50-100 USD
245
$25 to $100, depending on condition.
50-100 USD
$50-$125
They sell new for $125.00.