A person manages an apartment building, renting apartments, collecting rents, etc. Under which condition is that person NOT required to have a real-estate license?

This situation does not exempt the individual from needing a real estate license. Even if they do not sign leases themselves, if they are facilitating the rental process, they may still be classified as acting in a real estate capacity, which typically requires a license.

Living in an apartment rent-free as compensation for managing the property does not exempt a person from the requirement of a real estate license. This arrangement provides a benefit, but it does not change the legal requirement to hold a license if the person is acting as an agent in a property management role.

Managing multiple properties for different owners typically requires a real estate license, as this individual is acting in a professional capacity that involves managing real estate transactions on behalf of others. This scenario does not fit within any exemptions that apply to employees of property owners.