the so called pole building here is the norm for barns/garages. treated 4 x 4 or 5 x 5 's. the poles are set upright in the ground, those are your "foundation".
my home is of that construction. I describe it as "rustic"!!! no problem with insurance, I have to pick my ins. co. as far as wood hear is concerned tought.
if I sell, NOT eligible for trick govn't FHA financing, as it is not considered " conventional" construction. I would have to find a buyer that actually has some $$. or finance it. Ha