A:Answer Yes, you can add up to 15 cameras in a single Arlo base station/SmartHub. As for the difference between the Arlo Pro 3 camera with the Arlo Essential camera series, each of them has highlighted feature that suits to the needs of different customers. Example, if you are looking to get a camera with better battery life, the Arlo Essential XL Spotlight camera would be a good option. To learn more about the specifications of our products, please visit our website : https://www.arlo.com/en-us/default.aspx. ^RM