Arizonan here.
As s2mikon said, it varies from County to County. Somewhere, recently, I thought someone shared a guide to that which showed the laws in each AZ county...but I can't find that now.
Some places here in AZ have limits on how long you can camp or live in an RV, while some counties are the wild West still...and have no restrictions, or at least none being enforced. Generally, from what I remember, the more rural/ranch counties are the least restricted.
Even here in Coconino County, where I think the max limit for living in an RV on your own property <holds back rant...> is 100 days, it's pretty hard to enforce for a vehicle which is currently registered. Having an unregistered vehicle is a code violation, to keep junk from becoming an eyesore, but if the RV is registered then someone would have to prove you were living within it and not just parking it.