I sincerely hope this is a Turbine typo. They cannot be serious. Of course, it does say 100 Mitheril, but that equals 1000 TP....and that is just for 15 additional slots. Unreal!
I like a great many of the changes that were made including the ability to expand housing chests, but the price needs to come down. It shouldn't be any more than the account shared storage price. I also thought I read somewhere that the additional spaces could be bought for gold...which for me would be preferable to Mitheril or TP...but I cannot find anywhere in the chest to do so.