Honestly, I feel the reason for the increase in chest prize values has been due to the addition of new features to items. Fairy wings were the catalyst of this price increase. Being able to float with a cool animation increases the desirability of an item tremendously. I also think designers have been creating more player requested items. When designs are on trend and aesthetically pleasing this also creates more of a desirability, in my opinion. Its hard to have reasonable prices with a basically player ran marketplace. It’s volatile. Wild Wild West out here.