Once said auction house is introduced, you will start to see the economy balance out, values will become known, and those values will then only fluctuate up and down based on player base and new items introduced down the road/items becoming legacy and no longer available through normal means. For example, its generally accepted what candies and membership go for, but for pokemon, people trust try to price gouge. Honesty in the current system people who set an auction in trade chat are doing things fairest for now.