how to calculate tax liability when applying for TPT license in AZ

Dear experts, 

 

I have a rental house in AZ, I have a few questions would appreciate advices.

 

1. Do I need to apply for TPT licensee if I have loss in rental income after expenses? 

 

2. I am not aware of this TPT tax and forgot to pay this for last two years. what do I need to do?

 

3. when applying for TPT license, it asks to fill in this question:  "What is your estimated tax liability for your first twelve months of business?"  Does this mean the the actually rental income tax I owe (which is 0) ? or the TPT tax I owe (which is based on gross rental income)? 

 
 
TIA
Dave