If you need a space to be creative, you just might find it at Activspace. This unique establishment rents work spaces, workshops and studios at relatively inexpensive prices. All spaces have a window, a sink, a space heater and 24-hour access. Mailboxes are also available.
Berkeley Self Storage is a family owned and operated business. They have storage units that range from 2.4 x 2.4 to 12 x 40 and they can wait list you if the size you want isn't immediately available. The site also has a closed circuit security system and full time on-site resident managers. Storage-related accessories are available here and they also take e-mail reservations for the storage units. Berkeley Self Storage is affiliated with the Self Storage Association and Berkeley Chamber of Commerce.
Golden Bear Storage, covering a quarter of a block in West Berkeley, has a wide range of storage lockers. Units between 24 and 200 square feet are available. Clients who rent for three months or more receive an extra month free.