Why do price guides list different values for the same item?

Guides differ because they use different sources and methods. One may rely on auction results, another on dealer asking prices, and another on editors' estimates. Auction results themselves vary based on the sale, the audience, the region, and the condition of each piece.

Timing also matters. A guide compiled a few years ago may reflect a market that has since changed, while another may be more current. Some guides list values for excellent condition only, while others give ranges covering several grades.

When you see different values, read the introduction to each guide to learn how it defines condition and where its prices come from. Then compare your item carefully against the examples, paying attention to details like size, marks, and variations. Recent sold results for closely matching items are often the best check, and an appraiser or auctioneer can help when the item seems valuable.