Max size here for a no-permit build is 108 sqft (10m sq)....
In my rural township the building inspector is half an idiot and half a tin-pot dictator.
I wanted to build 10'x16' roll-off with two piers. The permit was $225. And he wanted drawings done by an engineering firm - my sketches, carefully drafted on my kitchen table, were ignored. He gave me the name of a local firm that would do that. I contacted the firm. Minimum fee for plans for a 160 sqft building was $500. Even if I drew them and they 'signed off' on them. Other firms were in the same fee range.
Building Inspector was very worried and confused about the roll-off roof. His first question was, "Why would you want the roof to be removeable?" I explained. He 'harrumphed'. Then he asked, "what if the roof were open and a storm happened and caught the roof and blew it into my neighbour's house?" and I told him the roof is closed and locked down in bad weather.... and he grumbled.
A friend advised me that I could apply for a variance to allow my specialized structure to be approved. The building inspector said, "You'll never get a variance if the roof isn't permanently attached." I pointed out to him that the whole purpose of a variance is to allow the 'different' roof. I asked if I could present my case to the variance committee and he said, "I am the variance committee."
And this is why I have a 9'x12' obsy with one pier.