Inherited a baseball card collection?

First, don't rush

Leave cards where they are for now. Don't throw anything out, don't sell the lot to the first buyer, and don't try to clean or flatten cards. Stacks held with rubber bands are best moved gently into a box as they are.

What to look for

• Age. Cards from before about 1980 were printed in smaller numbers and were often played with, so clean examples are scarcer.
• Rookie cards of Hall of Fame players, which are usually the most sought-after cards of a player.
• The late-1980s and early-1990s boom. Cards from roughly 1987 to 1993 were mass-produced. Most are worth little, though a few stars and rare variations are exceptions.
• Graded cards already sealed in plastic holders with a label and grade.
• Sealed packs, boxes and factory sets, which can be worth more unopened.
• Autographs and memorabilia cards, and anything that looks unusual or misprinted.

Condition matters more than most people expect

Two copies of the same card can sell for very different prices depending on condition. Look at the four corners (sharp or rounded), the edges (clean or chipped), the surface (creases, stains, scratches, gloss) and the centering (are the borders even?). A single crease can drop a card's value sharply.

Grading basics

Professional grading companies such as PSA, SGC and Beckett (BGS) authenticate a card, grade its condition, usually on a 1 to 10 scale, and seal it in a tamper-evident holder. Grading costs money and takes time, so it only makes sense for cards whose graded value clearly beats the cost. Most common cards are not worth grading.

Where real sold prices come from

Asking prices mean little. What matters is what cards actually sold for. Useful sources include eBay's completed and sold listings, 130point (which collects eBay sold prices, including accepted best offers), and the prices-realized archives of auction houses such as Heritage Auctions and Goldin. Match the exact year, set, card number and condition, or the grade if the card is graded.

Mistakes to avoid

• Selling the whole collection as one lot before anyone has looked for the few valuable cards.
• Pricing from asking prices instead of sold prices.
• Cleaning, trimming, pressing or writing on cards.
• Removing graded cards from their holders.
• Assuming every old card is valuable, or that none are.

This guide is general information, not an appraisal or financial advice. Market prices change.

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