Your business must register with ADOR before conducting any taxable business activity in Arizona for transaction privilege tax (TPT) and withholding purposes. The Arizona transaction privilege tax (TPT) is actually a tax on a vendor for the privilege of doing business in the state.The Business Personal Property Unit assists in the assessment of this type of property. Maricopa County sales tax details. Please follow the steps to become compliant. The three steps are: Step 1: Obtain a Transaction Privilege Tax license with the Arizona Department of Revenue. Certificate is to document and establish a basis for state and city tax deductions or exemptions.