By adding multiple roll up doors, a shipping container can be transformed into a multi-purpose on-site mini storage unit. The mini storage containers can be converted into a variety of configurations. Roll up doors can be installed in the side walls, as well as the front (end opposite the existing doors). The roll up doors come in many different sizes and types. The interior of the mini storage container can also be insulated and heated/cooled. Lights can also be added to illuminate the interior.