I'm not entirely sure, as I live in the city so would defer to others who are on the periphery or in the bush. But I guess the various volunteer fire services for one. Little in the way of architecture that I'm aware of. It's common if you're near the bush to have a cleared zone around your house, but the fires are so intense they often jump the clearings, and in any event that doesn't protect you from ember attacks. Back in the day they used to tell people to put cricket balls in the down pipes and fill the gutters with water to stop the embers getting under the eaves and into the roof of a place. But now, i don't know. They do as much as they can re notifying people - we have a pretty thorough danger rating system and the communications now are pretty bloody good, which I suppose is why there's been 20 odd deaths and not hundreds like Black Saturday only 12 years or so ago.
Insurance - well, premiums are high if you're in a bush fire zone, but as far as I know the companies do not refuse to insure at all. They're pretty aware of the consequences from a PR pov of refusing claims in circumstances like this. Which is unlike when Cyclone Tracey hit Darwin at Xmas 1974, and the insurers all said it was an act of god. Whitlam was on holidays in Croatia at the time and flew straight home, got off the plane and said to them "Act of God? This is an Act of Gough - you either pay the claims or you won't be in business next year." They paid.
I notice today Scotty from marketing has had a presser telling Australians and the world to holiday here. Obviously doesn't apply to government MPs, Ministers and Leaders.