Conflicting policies, regulations and codes exist in different counties and states. Confusion is understandable.
As I understand, in Pima County, the county in Southern AZ I dwell, codes are now in place for tiny houses on wheels to adhere to International Building Codes with a few exceptions like a second Ingress/Egress is not required because of the small square footage, a ladder is acceptable instead of a staircase with railing. Yet tiny houses on wheels can only be parked where mobile homes can. To me this is contradictory.
Possibly, I think people are under the impression that a tiny house on wheels is considered a second dwelling, therefore they are not permitted to park it on there property in addition to their primary home. As far as I am aware, a tiny house on wheels is not a permanent structure and should not be viewed as a second dwelling. Also in my view, if the Department of Motor Vehicles requires it to be permitted as a travel trailer then it should be considered a recreation vehicle for parking purposes. I admit all of this conflicting info is confusing to me.
Before buying check out the policies in your area, be prepared.
I recommend before you approach public entities in your area, check out the codes and regulations for yourself. The tiny house movement is in its infancy and it seems to me everyone is struggling to define exactly how to classify tiny houses on wheels and to regulate them. In my understanding they should not be considered a second dwelling unless the wheels are taken off and it is put on a foundation of sorts.
All that said, be creative! If being a tiny dweller is what you desire, look at all possibilities all angles. Good luck!