Making retainers & isearch easier to use

Would be awesome if we could access all the inventories of our retainers from one interface, instead of having to call them back and forth individually. Even in-game that would make sense: Our retainers manage our storage, but which one we call to fetch us something does not matter.

The same way, selling something from the retainer inventories with a specific retainer would happen through one interface as well (instead right now sometimes calling retainer #1 to fetch the thing and then calling retainer #2 to sell it).