[I need some direction on finding the value of a Winchester Mod 1892 in very good condition.]
Start with a set of good, clear digi pics.
They will stand you in good stead, should you decide to ever sell it online, after any appraisal.
You would be best served by presenting (to any appraiser who cannot do a "hands-on") good/clear pics of both sides of the rifle, and pics of receiver/stock details to define condition in an appraiser's eye.
Appraisers want to see an overall pic for config, a closeup pic of the sights for originality, and of the metal & wood for rating their condition.
A description of the bore's internal condition is usually desireable, too.
Also, a complete description of the rifle's exact markings/stampings, and their location(s) help determine if it has any special/premium value.
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