I recall that GotT went from 4e~5e to 10e a few years ago, and then dropped to 7e~6e as of now.
Sadly, everything that can be generated and that a lot of players want is probably botted right now. The prices only reflect how badly people want them and how many bots are botting them.
I agree with Red. Limited minis and pre-nerfs are the way to go. But people owning these (especially the good ones) have little reason to sell them. Whenever something comes to an auction, prices skyrocket out of a normal player's range of paying ability. If you don't own something to begin with, the only way to win these auctions is real-money trading or botting, which in my opinion is pointless, and also against the game rules.
All things considered, I would suggest simply spending currencies on things you like. Get that cool weapon skin. Get that armor. Get the most enjoyment out of the game. What you enjoy has the most value in this game.