Since you are not engaged in a retail business for which sales taxes apply to your transactions, how are you affected by this requirement other than to obtain a license to operate a rental property?
Montgomery County MD requires landlords to obtain a rental dwelling license for each rental they operate with the license jurisdiction. License fee for me is an annual charge of $56. No “sales tax” on collected rents, though I do pay income taxes on my net rental income.
I believe that the rental tax and the rate is not county but city specific. This may be new for the city of Avondale, but is certainly not new for Arizona. Many cities in Arizona have a similar tax.