When there is no data the seller and buyer create the data. You have money you want the card. How much money would you trade for the card? The seller has the card and may want money. They likely have a number in their head that they’d take. Start the negotiating. The £16k acts as a ceiling for negotiations.
I have a 1st edition base set Charizard in French and 2 guys have offered me 10k usd (3 months ago)(declined).
I think (my opinion) that the price of Spanish pokemon cards are a little less than the French ones.
I guess that now the price of Spanish Charizard is 7-9k usd (on eBay)
What I ment by that was not about the price, just about the low pop. I do’t feel other languages were heavily graded over the years to state pop 7 is like a super rare and hard to grade card, something similar to no rarity base
the print quality of spanish base set was worse compared to german or french base set, so I can see a PSA 10 spanish charizard fetching a premium for that
Im from Spain the low pop it’s because we play with them a lot so many are so poor quality and really rare to find one I have a 9 bought for 60 € 3 years a go the 10 Italian guy ask me for 1k didn’t buy at the time now I regret
Quality of printing was worse and all spanish play with them trade them no sleeve protection I was 13 I sow it with my own eyes I buy many and sell all at the time keep a venasaur and grade it got a 10 Blastoise a 8 and bought a 9 Charizard