Self Storage Portable Units/Equipment?

[Josh Smith]

Hello, I'm in the process of purchasing a 20k+ Sq ft warehouse/bldg and would like to use part of it for self storage. Id like to use floors 2-4 for smaller storage units (5x5, 5x10) but am limited to the size of freight elevator to move storage units to these floors for install. I'm looking for ideas or insight to see if there is a secondary market typically for portable units like this? I'd like to by used. How flexible are these units to collapse and move typically? Any advice or ideas help. Thanks!