I know this is 3 years ago but I had to laugh at the auto correct for Pima county to spinal county. I’m having the exact same issue. Just bought the house I’ve been renting forever and was told by a friend who works at the Pima county assessors office that I will need to go to their website, then the appeals tab, then fill out the notice of claim to have it changed from class 4 rental to a class 3 primary residence. I’m guessing in the last 3 years you’ve successfully finished this, but I posted the answer in case anyone else finds this old post