[SoundWave88]

I keep my boxes for rare and exclusive stuff that I open, or bigger boxes. Transformers, for instance, Amazon Unicron and most recently SDCC Bruticus, Masterpiece boxes, Voaygers. I do keep the card backs from blister cards, but throw the blister itself away for both MU and Transformers. 'Course, I am new to this and I don't have a decades worth of cards and boxes. I say through them in a tote, store it, and if you need them, they are there. Now the question is, do you flatten the boxes for more room or not??

People do sell boxes for old toys, and if in great condition, go for some money for completist out there. (Who knows what current toys will do though.)

Edit: Ahem (Who knows what current toys will do that are not rare and exclusive items though.)