To quote from the pre-publication PDF they gave me with my pre-order:
Items of Power
Items of Power is a catch-all category for abilities that are derived not from the person himself, but from the magical equipment he brings to the table.
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If the other PCs are getting items of power, in theory this how you make them pay for it.
But that's not how I'm thinking of going. I'm thinking of allowing a minor slot (say for a potion) "for free" - that is applying the +1 to something that only costs -1 for a net of 0, but only if it's that's the only thing they are carrying. If they want two minors or a few majors then I'm thinking of coming up with something like a refinement, but something that you don't don't need a power to have... If they are "Pure Mortal" I would definitely leave them that way.
Basically, play balance falls apart if some people get free lunches and others have to pay. If Tom the Wizard spends weeks of downtime making impressive magic items for himself he's limited to a certain number, so if he spends that time making items for Dick the werewolf and Harry the scion then Dick and Henry would have to pay for their bonuses. Otherwise they are getting magic items at no cost while Tom is still limited by what his powers say he can have.
Of course if people have to pay for items it matters who uses it. I can foresee cases where X has it the item on his sheet but it makes sense for Y to hold it, which is an issue if Dick and Harry are basically acting a mules for Tom's magic items...
Theme wise... I can't help noticing that Dresden doesn't handout magic items to his friends and allies. He has his duster, but Murphy doesn't have enchanted armour. He will sometimes share a potion (like he did with Susan), but he doesn't hand them out at the start of a mission.
Take the "we load up for bear and go into the Black Court lair" bit where he almost lost his hand - Dresden didn't hand out magical protections then. He didn't ask his wheel man if he had any minor magic items to hand off. Sure, he'll do things to let people see fairies, but Dresden doesn't share magic.
Now I'm wondering why. Is it a trait of Dresden's or is it something more... Elaine doesn't give her charges minor magics to protect them in White Night... Thinking about the books Wizards don't seen to hand out minor magics unless someone really, really needs them (like the Gatekeeper did when Dresden needed to see).
Richard