DO NOT let your items sit on the ground for long. White items seem to decay after about ten minutes in town, this includes gems and pages. I found out the hard, expensive way.
Stack your master characters hitpoints. This will help when you need to resurrect anyone that dies during battle. It can be disorienting when you need to res from a slaves screen.
Use an upgrade waterfall. Give all the items to one character and decide what is best for them, then drop everything that wasn't equipped and do the same with the next character, and so on.
Upgrade the blacksmith and jeweler on one account only. There is no need to spend the gold on the others, everything can be traded.
Make mules, upgrade stash sparingly. Store gear on a bunch of lvl 1 characters. This saves gold at the expense of time.