Property management licensing requirements vary by state. In most states, a property manager that is renting or leasing properties is required to have a real estate broker's license or be a real estate salesperson working for a licensed broker. There are some exceptions to this rule including onsite managers who work at one property, community association managers, and short-term rental managers.
The main reason most states require licensure for property managers is to prevent legal liability for property owners. Licensed property managers undergo a background check and are trained in the laws against tenant discrimination, property accessibility for individuals with disabilities, and confidentiality laws. The only states that do not require property managers to be licensed are Vermont, Idaho, and Maryland.