What is a black prince bridge company 20 gauge single shot shotgun with serial number a689272 worth?

The value of a Black Prince Bridge Company 20 gauge single shot shotgun can vary significantly based on its condition, rarity, and market demand. Generally, these shotguns can range from $100 to $300. If the shotgun is in Excellent condition or has historical significance, it could be worth more. For an accurate appraisal, it's best to consult a firearms expert or appraiser.