Also how will you go with the owner builders license?
Is there a minimum age limit to getting one?
Can you get one even if you are not (I assume) the "owner" of the property?
I'm just playing devils advocate here, but might be worth checking out.
Also FC, is the property classed as rural? When I put up my "rural storage shed" (steel framed) I had to put it through council, but I didn't need to get an owner builders license or anything.