Vendor registration is free. In order to enter into a contract with Miami-Dade County a firm must be fully registered.Form 3921 must be submitted along with the 3 supporting documents described in part 1 of this presentation as a single application package. Complete the City's Vendor Registration and IRS W9 Form. Without the prior written agreement of The School Board of Miami-Dade County, Florida. In no event should vendors disturb teachers who are in the classrooms. Vendors selling products pursuant to labor contracts, such as insurance, annuities, etc. Every business needs to obtain a Business Tax Receipt to operate in the City (also known as an Occupational License). Net or can be faxed or mailed to the address provided on the application.