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They have a vested interest in maintaining/expanding their business so just like card grading companies, they understand it's ideal for them to "create value" out of nowhere and if an auction sets a new record, it's not like they have to worry about due diligence to see if the price made sense or who the seller and buyer are and if they have a preexisting relationship or what, they just take their cut and that's it.

From my own experience, when I was living in London Spanish, Italian and French cards were valued slightly lower than their English counterparts, both on player-to-player trading and on magiccardmarket.eu, and for both non-foils and foils including eternal staples like Thoughtseize

The biggest planeswalkers like Karn Liberated and Ugin, the Spirit Dragon

Wait for stable market trends

The model would either not respond or confuse cards, miss some or even hallucinate prices