Price guides
When a price is stale
Checked

Every price has an age. A number checked yesterday tells you more than one from months ago, especially for cards that move quickly.
Read the quote date
Holo Folder shows when a price was recorded. Look at that date before you look at the number.
Treat missing as unknown
If there is no usable evidence, the app says so. Unknown stays unknown. That is a prompt to look further, not a reason to assume a card is cheap or expensive.
Check per-printing history
Recorded history for the exact printing shows how its price has moved over time, which can put a single old quote in context.
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