The Gardevoir (6 / 113) card can be found in the Delta Species set.
Recently sold 2 times and based on those sales is worth around £20.94.
Currently, there are 4 open listings for this card on ebay.
This card sells in the range of £20.33 to £21.55, making it very stable.
This Rare Holo card was illustrated by Mitsuhiro Arita.