Something I realized long ago as I started making money with music - and getting some serious bouts of G.A.S. - was that along with purchases of exciting new gear I would inevitably be exchanging or selling back gear I had outgrown or just didn't work out for some reason.
It took me quite a while to realize that whenever I purchased new gear, throwing away or recycling the box was an extremely short sighted thing to do. Keep that in mind when I state what should be the obvious - whenever possible, don't throw away the box!
If you ever decide to sell a piece of musical gear, chances are that you'll be looking to unload it online. Having the box that it came in will get you much further along when packing it up for safe shipment, especially if you're sending something fragile like a microphone or monitor speakers.
Even if you sell the item locally, it's going to be a much better presentation if you still have the original box. Not only does the box make the item more attractive, you'll give off the impression to the buyer that you're a person who takes care of their gear, so you'll look more attractive too.
Obviously if you have a small space you might not be able to find a place for even a set of broken down boxes. Oh well. But I would encourage finding room for any items a few hundred dollars and up, because that useless piece of cardboard could be worth a lot of money when reselling.
For myself, I've sequestered a space in the garage just outside the attic. If I ever have to sell, I just need to knock it down from its perch and shoo out all the spiders. Good as new!
Until next time,