Thanks for the insights. RagnarD I was going off the NBNco website about the router. They said it 'possibly' won't work???
$500 is ridiculous. That is why I started investigating. It was thrown in at builders interview with no time to research so we felt we had to have it but in reading the NBNco stuff they say they do the first install and give you the items through a supplier as they are wholesale. They said this is if at time of roll out. Still confused on what we actually get from NBNco as I know builder is doing conduit to house and then in roof and double power point. Bit expensive.