The reason I clump banking and mailing together is because with the right setup your mailbox can become a second bank. With the wrong setup it can become an absolute nightmare for you. Let's show you the setup first and then go over the reasoning behind it, that's less boring I think anyway. And no sorry I don't have a product per se on the subject, though my gold guide is pretty good if I do say so myself!
Army of Alts Breakdown
- The Buyer and Distributor - Purchases mats from the auction house and sends it off to the crafters and cooldown users.
- The Crafters and Cooldown Users - Take raw mats and transform them into working products to be sent to the posters.
- The Posters - Post items and collect money to be sent back to the buyer/distributor.
I highly encourage you to have several guild banks between your toons in order to maximize space in exchange for having to mail items more frequently between characters. If you need a refresher course in bank alt math please check this post.
So now you have the correct setup for your toons and the buyer/distributor purchases a few hundred stacks of saronite ore. Instead of those stacks taking up bank space you can simply leave them in the mail until needed by the other soldiers in your alt army. This will not slow the accumulation of wealth since that's being taken care of by your posters and it will not slow the production of crafted goods because that's being handled by the crafters/cooldown users. Effectively you have created another bank with the buyer/distributor's mail box.
What's your auction house mail and guild banking setup? There are definitely alternatives to my own setup so please share in the comments to give some examples of these.