when did this card in an 8 go for $400+? i remember a couple years ago it was like a $100 card when i was buying them for signings. i know the postwar market kinda got stupid but this common card 4x price-wise in a year? who's buying them? checking completed auctions it was still around $150-$175 back in may....super weird they actually decreased in value when you put a signature on it

signed sp went from $500-$600 a year ago to around $400 today.