Legal Question in Landlord & Tenant Law in California

You have to be licensed to take charge an owner money for the sale/lease of a unit, but not to take money from a tenant. If you had to be, a majority of leases would be invalid as most rental units are owned and operated in a mom and pop style. Why would you think these three categories would need a license? Do you need a license to sell your car, at home cut meat to make a sandwich, etc?

Even if a license was required, it would not void the lease. Transactions are not void just because one of the parties does not hold a regulatory license, although in some professions lack of a license precludes the unlicensed practitioner from collecting payment for their work. If I brokered a sale of a house between you and a third party, your contract with them would not be invalidated, I would just be in trouble and might not be able to collect my commission. In the specific situation you cite, the reason no license is required is because the people involved on behalf of the landlord are employees. Employees do not need to be licensed to engage in real estate transactions on behalf of their employer. If they were an independent broker/agent, it would be a different story, but apartment managers are almost always employees of the landlord, or employees of a licensed property management company.