
From what I know, retainers (which you can hire at the retainer desk at your local market in your city-state of choice) hold a lot of items as well.
As far as "banks" go, I do know that Free Companies will have their own storage as well. Sort of like a guild bank in WoW.
As far as "banks" go, I do know that Free Companies will have their own storage as well. Sort of like a guild bank in WoW.