Broker employment question
I have a quick question regarding the paperwork to accept employment at a commercial brokerage. I know that because brokers are considered independent contractors, there's no need for a form I-9. However, what sort of documentation do you need to provide to accept employment at a commercial brokerage (more specifically the big 3)?

I am wondering because I am in the process of renewing my employment authorization and I'm worried I might not be able to accept an offer because I don't have the document yet. Please let me know. Any insight will help.  
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