Show learned pminions/mounts/barding in item description

[Zumi]

You could do something like FFXI. If you don't know a spell in FFXI the letters of the spell appeared in gold, while if you already knew a spell the letters appeared in green letting you know you already know that spell and don't need to buy another one.

[Sakuraluna]

Great idea. I swear I've accidentally re-bought one or two at some point even after looking through the minion guide. D:

You could do something like FFXI. If you don't know a spell in FFXI the letters of the spell appeared in gold, while if you already knew a spell the letters appeared in green letting you know you already know that spell and don't need to buy another one.

This would be an awesome idea for a solution.

Or either add a function if you right click on it from the mb and do a search, that would highlight it in your minion guide if you already have it. Or even just an alert flashing across the middle of your screen and/or a checkbox "You already possess this minion, do you really want to buy another one?" Or something. Glad that it's being looked into.