My idea for a store bought item is a "buff button"
Buff buttons come in 5, 10, and 15 slot varieties.
A buff button can only be configured once, so choose wisely!
To configure a Button, simply drag the desired buff spell into an open buff slot and select whether that spell should be extended or not.
Once configured, the buff button could be activated within "hireling" distance of a zone entrance. Activating the buff button causes each buff to be sequentially applied. Any buff that is not currently castable is skipped (e.g. Not a memmed spell, no longer have extend, out of mana, etc.). Mana costs are determined based on the character state when the button is activated.
In addition, the store sells minor, normal and greater buff button solvent that can be used to reconfigure a buff button.
I would buy this in a heartbeat!
J