I suggest making all the monthly Cash Shop challenger items that are multiple use be "magical" until some one has used the unlock challenger feature of the item. once used the item would no longer be "magical" and would not be able to used to unlock the challenger if ever sold, given, or traded to a new owner but would still be available to use the "other features" of the item.

I don't know that this is really necessary, as the items would probably be just as expensive.

But I know it has been suggested before that for items that unlock challengers, change the "Unlock" button to say something like "You've already unlocked this challenger!" so people don't accidentally use it twice and waste their item.

i was more talking about the fact that if you put said item in your wardrobe then you can not use it to unlock the battle challenger

Eh, it's like asking to have cash shop theme items "magical" too. I mean items like If you transform it into a plushie/beanbag and put into collection there's no taking it back to put in the wardrobe either. You want multiple use, buy multiple items. I know it's not cheap, but it's apparently not supposed to be.

I have done this