I know every state and county is different, but if a customer wants to install their own small LED wall sign without any hardwiring into 120, just plugging into an interior outlet; typically, is any licences required?
How small? If it has a keyhole type hanger on the back, anything goes I say. But in my city, you (businesses, residents can do whatever as long as it's not business related) are limited to one typical open sign per store, but its unenforced. Just saying, it's plausible to have a sign that's lawful for anybody to install, but illegal for somebody to install.