Market research
See what available historical comparable sales suggest for a selected card, with every contributing comp and reason shown.
Pick each field from top to bottom. Catalog options are not limited to a player’s recorded sales, and you can type an exact card detail if it is not listed yet.
Start with a player, then narrow to the exact recorded set, rarity, subset or parallel, and CC. Compbook will not show an insufficient-data warning until a complete estimate is submitted.
Methodology
Compbook Market Estimate is a deterministic comparable-sales research tool. It starts with direct field matches for player, set, rarity, subset/parallel, and CC. One direct sale is shown as evidence, but not converted into a range unless same-player support makes the result useful. Other cards of the same player, set and print run take priority over adjusted sales from other sets.
Topps NOW is hard-partitioned from regular products in both directions. Other-set price adjustments are used only when at least three players with comparable prices at the same print run support a consistent set relationship. Player similarity requires three shared card designs across two sets, with similar sale dates and prices typically within half to twice this player’s prices. It is not based on draft position. Other players’ raw prices never enter the estimated range. When calibrated evidence is sparse, the same player’s other cards at the same print run and card type can provide a clearly labeled, low-confidence baseline without a set adjustment. This requires three distinct sales across two designs: we use the last 120 days when sufficient, otherwise the last year. Older evidence remains visible.
The range uses the weighted 20th and 80th percentiles of contributing prices after supported adjustments—the lower and upper points of the central price evidence. Confidence does not add a discount or premium. Recent public cash transactions carry more weight; trade-valued, private, duplicate-looking, older, or weaker comps are downweighted. Severe outliers remain visible but are excluded from math.
Older 1/1 sales lose influence gradually, halving every 120 days; this alone does not reduce their recorded prices. Price adjustments require at least five matched repeat-sale card groups from the same player or supported peers. For 1/1s, the last 45 days are compared with the preceding year, and a rise or decline requires at least 80% directional agreement. Adjustments stay within the observed movement and are shown beside each affected sale. If the usable evidence is sparse or the range would exceed 1.8× from low to high, Compbook shows comparable evidence without a price range. This limit is a usefulness rule, not statistical certainty.
