Vaporeon

Vaporeon (25/108), the Uncommon from Dark Explorers, has an estimated ungraded market price of about $24–$32. Note: 18 other cards named Vaporeon exist across the sets Riffle tracks, at very different values; check the collector number.

This page covers Vaporeon (25/108), the Uncommon (about $24–$32) from Dark Explorers.

The other versions: #H31/144 from Skyridge (Rare, about $370–$480); #33/144 from Skyridge (Rare, about $155–$200); #19/115 from Unseen Forces (Rare, about $140–$185); #25/100 from Sandstorm (Rare, about $105–$140); #20/116 from Plasma Freeze (Uncommon, about $42–$55); #12/64 from Jungle (Rare, about $41–$55); #34/100 from Majestic Dawn (Rare, about $34–$44); #28/64 from Jungle (Rare, about $31–$40); #52/95 from Call of Legends (Uncommon, about $28–$37); #TG02/30 from Brilliant Stars Trainer Gallery (Rare, about $27–$36); #41/90 from Undaunted (Uncommon, about $22–$29); #34/111 from Rising Rivals (Rare, about $17–$23); #42/236 from Cosmic Eclipse (Uncommon, about $6–$9); #22/98 from Ancient Origins (Uncommon, about $2–$3); #18/68 from Hidden Fates (Rare, about $2–$3); #134/165 from 151 (Rare, about about $2); #30/185 from Vivid Voltage (Rare, about $0.80–$1); #022/131 from Prismatic Evolutions (Rare, about under $1).

The collector number printed at the bottom of the card is the reliable way to tell them apart.