Vault
From Outwar Wiki
The Vault is where you can store valuable items that you can't equip yet or cant send to another player yet so you can collect more items in Diamond City. All items stored in the vault are protected and cant be accessed by anyone else.
The initial size for the vault is 50 items, For 150 points you can upgrade the size to 100 items, And for 499 points you can upgrade to 200 items.
