I'm sure this is a very stupid question, but ...
.. what's the story with street numbers?
I found ours on land.vic.gov.au but does that mean in theory I could go to our block, whack up a letter box with "14" on it, and start receiving mail, even though there are no completed houses with letterboxes in our street yet, and all other signage has lot numbers?
Is there some kind of formal process you have to go through with the council or Australia Post, or...???