Legal Question in Business Law in California

She is correct. A business license is connected to the actual physical location where business is conducted. This is relevant to make sure there is compliance with zoning, as she mentioned. It is also relevant sometimes to taxes and other aspects of government laws, rules, regulations and taxes, that may be location specific within a city.

Some people dodge this by using a UPS or similar mailbox service and putting "suite" or the like in front of the box number, instead of "box." That is definitely not legal, but I don't know of anyone who has been nailed for it. The other option is what I did when I first set up shop as a solo attorney, which is to get a virtual office plan with an outfit like Regus or Pacific Business Centers. They not only give you a physical address, but also offer a lot of handy business services, including rent-by-the-hour offices and conference rooms, package receiving, copy services, and a real person to answer the phones and put callers into voicemail that you can pick up anywhere (or for a higher fee they will actually call you at any number you designate and if you pick up they can transfer the call as if you were really sitting in an office down the hall).