Licensing is the legal permission to use a photo over a set amount of time. In real estate photography, this contract is set between the photographer and the real estate agent, and it gives the agent the right to use the photographs in their listing. This is a non-transferable license, meaning the agent cannot sell the photographs to a third party. Typically, the license will be active until the home has been sold, and all rights to the photograph revert to the photographer.
Not all states have the same licensing requirements, so it is vital that you research the requirements within your own state. As for pricing a license, this is also a unique variable with no set price. For example, there may never be the same deal for turnaround time, market real estate pricing, competition pricing, the area of use, and usage rights, to name a few. It will be at the discretion of the photographer to create a pricing guide for the license. For example, drone photography often requires licensing to safely photograph in accordance with FAA regulations. Some commercial photography requires permission and permits by the city and state.