Originally Posted by
Borrhavan
However, there really needs to be a way to unlock (inventory/vault)storage space in-game through quests or achievements and not only through the cash shop.
It isn't. At least not with the vault. You get 30 slots for free and you can buy up to 120 vault slots for in-game gold, and as such you can create (of course you would need a free character slot) a storage alt for another 120 slots.
Inventory in bags is indeed purchased in the store (at least expansion of it) but it is account wide, so every character on every server gets bigger bags with a purchase. Shared storage is also accessible for every character on every server. Contents of shared storage is limited to the server, but it is the same size everywhere.
Moved from Riddermark to Arkenstone on 9/29/2015!
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Disclaimer: The definition of "Soon™" and "In The Near Future™" is based solely on SSG's interpretation of the words, and all similarities with dictionary definitions of the word "Soon™", "Near", and "Future" are purely coincidental and should not be interpreted as a time frame that will come to pass within a reasonable amount of time.