Are you aware that your build might have extra costs to meet the requirements of Bushfire Attack Level (BAL) assessment/report being obtained and being below a certain level to ensure building is less prone to bushfire loss.
These requirements monitored by the local council could add thousands of dollars to your build costs.
More information might be obtained here along with map of prone areas.
The building standards are not retrospective. Only new class 1, 2, 3 or 10a buildings (and additions/extensions in certain circumstances, see below) in a designated bushfire prone area will need to be built to the BAL construction standard.
There are exemptions in place for additions and extensions, including if the building works is under $20,000 or the proposed extension/addition does not impact the bushfire risk.
You can find out more about building in designated bush fire prone areas from the Building Commission’s website (http://www.commerce.wa.gov.au/building-commission/building-designated-bush-fire-prone-areas).