VALUE METHODOLOGY

How IQCardGuide turns sold comps into useful value estimates.

The goal is not to produce a magic number. It is to use repeatable rules so raw values, graded values and grader premiums are based on transactions that are genuinely comparable.

Sold-comp checklist →Raw vs. graded method

STEP 1

Identify the exact card before using any sale.

A close-looking card can still be the wrong comp.

Match

Year and set or product
Card number
Parallel, refractor, variation or print
Autograph or relic designation
Raw or graded status
Grader and exact grade when graded

Do not mix

Different parallels or serial-number tiers
Raw cards with graded cards
Different graders or grades in one bucket
Obvious altered, damaged or misidentified examples
Lots containing multiple cards unless the individual card value is clear

STEP 2

Use completed transactions, then screen the context.

Sold does not automatically mean usable.

Prefer recent salesStart with the most recent relevant transactions. If the market is thin, widen the window and label the longer period clearly.

Use the actual transaction price when knownDo not substitute an asking price for an accepted sale. If an accepted-offer amount cannot be verified, do not treat the original list price as the sale price.

Normalize obvious shipping differencesWhen practical, compare the amount required to acquire the card before tax. Large shipping differences can distort otherwise similar sales.

Review unusual resultsAn extreme sale is investigated before inclusion. Misidentified cards, damaged copies, poor listings, suspicious bidding or bundled lots can make a transaction non-comparable.

STEP 3

Build a raw baseline and a graded baseline separately.

Within each card, IQCardGuide favors the center of several comparable sales rather than letting one transaction dictate the result.

Raw baseline

Use recent raw sales for the exact card, screening for condition when photos or descriptions make obvious differences visible. The raw reference should represent a typical market copy—not the cleanest raw card ever sold and not a damaged outlier.

Graded baseline

Use sales for the exact grader and exact grade. PSA 10, BGS 10, BGS 9.5, CGC 10, SGC 10 and TAG 10 remain separate comparison buckets.

Preferred within-card reference: when enough good comps exist, use the median sale value for the raw bucket and the median sale value for the exact graded bucket. The median reduces the influence of one unusually high or low sale.

STEP 4

Calculate the percentage premium card by card.

This prevents expensive cards from dominating the grader comparison.

For each cardPremium % = ((graded reference − raw reference) ÷ raw reference) × 100

Example: if the raw reference is $100 and the graded reference is $225, the graded premium is +125%. The published comparison focuses on that percentage, not the $125 difference.

Then calculate the IQ average

Each qualifying card contributes one card-level percentage. IQCardGuide averages those percentages for the grader/grade being studied. A $5,000 card therefore does not receive more weight than a $50 card simply because its dollar spread is larger.

When useful, we may also show the median card-level premium as a stability check, but the headline metric remains the average percentage premium.

PUBLISHING RULES

Every percentage needs context.

Always show

Grader and exact grade
Average premium percentage
Number of cards in the sample
Sales window used
Last-updated date

Label thin data

If a card or grader has too few comparable transactions, IQCardGuide should say the evidence is limited rather than manufacture precision.

No-data is better than fake-data.

Keep card-specific comps primary

A grader-wide average is context. For a specific card, its own recent completed sales remain the strongest market evidence.

IQ RULE

Comparable first.
Average second.

A mathematically perfect average built from bad comps is still a bad answer. IQCardGuide prioritizes matching the card and transaction before calculating the percentage.

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