How we price.

What alpha actually uses today

Official eBay sold-comps access was denied through Marketplace Insights, so alpha does not rely on it. GrailSpy uses a shared collection of public eBay AU sold-listing observations where available. Cards without eligible sold evidence use labelled Australian active-listing asking prices. Sold records and asking prices are kept separate.

The sources

Every valuation on GrailSpy is drawn from these signals, in this priority order:

1. Reported eBay AU sold prices. Public listings marked sold, collected once for all users. Source links, observed prices and sold dates appear on the card page. The public page does not prove payment, settlement or that the transaction was not cancelled. Hidden Best Offer amounts, explicit foreign-language cards, ambiguous printings and lots are excluded. One listing ID contributes at most one observation, even if it sold multiple copies.
2. Active listings, identity-matched. The working alpha estimate when no in-window sold history exists. Same set, same number, same finish. Asking prices, not sales — surfaced because thin data still beats no data, and clearly flagged as provisional.
3. Title-match fallback. Looser match across recent active listings when nothing above is available. Broadest coverage, weakest signal. Also flagged as provisional.

What we adjust for

• Condition. Four buckets — NM / LP / MP / HP — parsed from listing titles. NM is the baseline. When a non-NM condition has fewer than three sold comps in the window but NM is direct, we extrapolate using fixed industry-heuristic ratios (LP ×0.85, MP ×0.70, HP ×0.50) and label the slice as extrapolated. These ratios are placeholders — they will be retired once we have enough AU sold data to learn the real curve.
• Card price only. Postage never changes a median, bargain percentage or alert threshold. Public displayed item prices may include eBay's Buyer Protection fee; they are not the seller's net proceeds.
• Currency and location. The active-price baseline requires a known Australian location and native AUD currency. Public sold searches must visibly have Australia-only and Sold-items filters, and show an unambiguous AUD amount. Those public search fields are weaker evidence than a native-currency API field, so the source is labelled.

What we surface

• Median price — the middle of recent sales. Less skewed by outliers than the average. Trimmed: sales outside [0.5×, 2×] of the initial median are dropped before the final median is taken.
• Sample size — the count of in-window parsed comps for the primary condition before outlier trimming. Always shown. Drives the confidence flag. Three records in one condition are required for a direct median; fewer records remain visible without a direct estimate.
• Confidence — a limited-data badge fires when the primary condition has fewer than five in-window comps. Anything at or above five is unflagged. We do not surface a "high confidence" label — alpha samples are too small to earn one.
• Trend — when both a 7-day and a 30-day window have data for the same condition, the ratio is labelled rising / falling / stable with a ±5% deadband around 1.

What we don't do

• We don't extrapolate aggressively. If the data is thin, we say so on the row.
• We don't quietly mix asking prices with sales. When we fall back to active listings, we mark the result provisional.
• We don't conflate raw and graded cards. Alpha pricing covers raw NM/LP/MP/HP only — PSA / BGS-graded valuations are not yet in scope.
• We don't forecast. We report what happened in the window and flag the shape of it. You decide what happens next.

Coverage and freshness

Public sold dates have day precision. Collection is periodic and covers a growing selection of shared searches; it is not a complete live record of every Australian sale. Check the last observation date and source listings. A collection error does not mean that no cards sold.

The AU TCG market is small and noisy. Sample sizes are limited. Our confidence flagging is conservative on purpose. When a card has no in-window sold history we either fall back to provisional active listings or render the value as unavailable — never as a fabricated zero.

Questions?

Email privacy@grailspy.com.au. We'll tell you what we know and what we don't.