JJ,
Wickipedia is correct - the two are synonomous. "Mini Storage" is more 70's and the term got a bad rep because of poorly-built facilities with ugly orange doors. "Self Storage" is the more modern term and the hope is it brings to mind more modern facilities with well-built, user-friendly facilities with security and tenant convenience in mind. "Mini Storage" is more reminiscent of the "build it and they will come" era. I believe that "Self Storage" denotes the mature era - more thought-out and built with the advice of professional expertise. Converted warehouses are usually "Climate Controlled Self Storage" with an attempt to keep temperature and humidity within a limited range conducive to safer storage of personal property - less damage from mold and temperature extremes. "Self Storage" is the sexier, more politically correct term for modern facilities. Some even like to work "Storage Systems" into their names.
Steve Smith
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SteveSmith@ByteOne.com