Plan A: Store it at Mom's house.
Plan B: Marry well and "let her" to buy a 4500 sf house, build yourself a 4000 sf (guys only) pole barn w/AC office and indoor parking for your ATVs, ultra-light and two seat sports car. That is your private storage. This is not likely to occur if you had the Plan A option available to you.
Plan C: Leave it in your van. When I got my apartment, I quit living in my van so this method worked out well for me. You could also park the van behind the pole barn if plan B worked out.
Plan D: Scatter it around the house, utilizing parts of it as furniture. Fins work well to bolster up a sagging couch, wetsuits make oh-so-comfy floor mats for standing and working in the kitchen. Masks have many uses. I have seen lovely floor lamps using an Alu80 as a base. Lead weights may be used to communicate more effectively with your downstairs neighbor. I still haven't found an alternitive use for the BCD, so I just wear it around my apartment like a vest. Chicks dig this. Just show 'em your saftey sausage- failing that, whip out the ol' pink snorkel. Dive knife? You need to open cans of beans, right?
Plan D: Stuff it all very tightly into a black canvas duffel bag and use it as a bean bag chair.
Plan E: Box it up and mail it to yourself via Parcel Post. It's very slow and cheap and they'll hold it at the local USPO for weeks (because they can't get it into your mail slot at the apartment) before returning it to sender (you), the cycle begins anew and they'll have to hold it for another few weeks. I do this all the time with our Ferrets when we go on extended dive trips. Used to do it to the kids but they passed all those pesky laws.
Necessity is a mother.