Source Roles
TCGplayer is the primary pricing source for condition-aware SKU and product pricing. CardTrader contributes marketplace listing and inventory pricing from filtered listings. Cardmarket is used for EUR market context and cross-market validation where exact mapping exists.
Card Kingdom is validation only. It can help compare retail or buylist context, but it is not averaged into NeoPrice.
Print, Finish, And Condition
NeoPrice is version-sensitive. Set code, collector number, finish, treatment, language, product source, condition, and seller depth can change whether a price is useful.
Representative card pages should not use one scarce premium version to describe ordinary deck copies. Exact-print pages preserve printing-specific facts.
Missing Data And Outliers
Missing price, inventory, seller count, listing count, or source coverage is missing evidence, not zero. A source-provided zero remains valid only when the source actually reports zero.
When marketplaces disagree or a move looks isolated, NeoCardAlpha shows the uncertainty instead of hiding it behind one clean number.