Legal Question in Real Estate Law in California

It would be wiser to advertise the exact zoning classification, e.g. "R4" rather than to characterize it as just "residential" or "commercial." Among the reasons are that some residential zones also allow limited commercial use, such as home businesses or neighborhood stores. However, I'd also add that if the zoning truly prohibits all commercial uses, then advertising it as "commercial" is improper and probably fraudulent if the person doing the advertising has a duty to investigate, as would a licensed real estate salesperson.