Definitely this is a state specific question. In Missouri, the brokerage name and number do have to be on all signage. The theory is that the customer must always have all the info they need to contact the broker, in case they have an issue with the individual agent or cannot get in touch with the agent. It's all about protecting old JQ Public.
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REALTORŪ, Broker/Salesperson, GRI, ABR
REO listing/selling since 2004; BPOs