Thanks everyone for these incredibly helpful comments. I've been out of Internet access for a few days, hence this late response. With a 150HP Super Cub, that by the time it is operational in Australia will have a long prop and tundra tyres on it, I'm really going to try and keep things as informal as possible. With good approaches, 200m of rough paddock is more than ample, depending on wind of course, so I'm house hunting at the moment and looking for something with a paddock like that. Then if I put up a prefab or a canvas hangar with no groundworks no-one should be much the wiser and I'm hoping I won't be surrounded by busybodies.
Thanks again -- I'm going to operate on the basis that if you don't ask no-one will tell you 'No'. Now, when I finally build that RV I would love to build for commuting in Australia it may be a different kettle of fish!
David