one more step......
As I understand first find a municipality that agrees on your plans.
If that's okay then buy land there and build.
I haven't heard of any obstacles using tires once you obtain a building licence.
Almost a year has passed, no progress whatsoever regarding municipalities in my case. I finally took the guts to put myself on the line and i will attack from another front! ;)
I'm finishing a yurt and going to live off grid in small plot that belongs to one of my family members.
Wish me luck! ;)
Good luck :-)