The Pikachu VMAX (TG17) card can be found in the Lost Origin Trainer Gallery set.
Recently sold 17 times and based on those sales is worth around £33.00.
Currently, there are 7 open listings for this card on ebay.
This card sells in the range of £25.32 to £40.68, making it quite stable.
This is a Rare Holo V card.
The fact that it is a VMAX card makes it one of the more valuable cards.