Some of the most expensive Pok?mon cards are the Pikachu Illustrator cards, the prerelease Raichu cards and a first edition Charizard from the 1998 "Trade Please" promotional campaign, as of May 2015. Prices vary based on the condition of the card.
The Pikachu Illustrator cards were released in Japan in 1998, and there are only six. One of these cards appeared on eBay for $100,000 in 2013. Even a card that isn't in mint condition is estimated to be worth at least $50,000.
Between 10 to 15 prerelease Raichu cards were created, leading to the card's high value. Each is estimated to be worth over $10,000.
A first edition Charizard has a suggested value of up to $700 in mint condition. Any first edition Charizard with a grade of nine or higher is estimated to be worth at least $300.
Other expensive cards include a rare holographic Charizard from the "Skyridge" set and a shiny rare holographic Alakazam from the "EX Crystal Guardians" set. The Charizard has an estimated worth of at least $600, while Alakazam is $330.
Japanese Pok?mon cards are typically the highest in value. The first edition Japanese cards, which have a higher value than regular cards, also have a first edition stamp on the card. The English cards originally had this feature, but it was discontinued.