Gengar ex #154 from 30th Celebration is a illustration_rare card that currently sells for about $71.33 ungraded, with graded copies ranging from $151 at grade 9 to $75.00 at grade 10. TCGrader's AI has graded 51 copies of Gengar ex (30th Celebration), averaging 9 overall. 86% scored 9 or higher, so clean copies are common and centering usually decides the top grades. A grade 10 copy sells for around $75.00 vs $71.33 raw. That's a modest premium, so grading only pays off for near-perfect copies.