A-1 Self Storage is one of the leading providers of self storage in California with 53 locations across California. A-1 is th ... e Self Storage division of the Caster Group, a third generation family-owned company headquartered in Southern California since 1959. The Caster Group specializes in acquisitions, development, and management of A-1 Self Storage, and other commercial properties in California. Its real estate portfolio includes over 4.8 million square feet in real estate properties. It is one of California’s fastest growing companies. read more