I'm looking for some feedback on a Sydney duplex budget I've compiled to make sure the costs are reasonably accurate. I'm new to building and have no construction knowledge or experience, so I've been lurking in forums and doing some research to pull together this budget. I'm hoping to get a good understanding of the potential costs before I start talking to my Bank and engaging an architect.
Some points of note:
- The Sydney block is ~660sqm with a 15m frontage, and Council has a FSR of 0.5:1
- There's a sizable easement (stormwater drain) cutting diagonally through the land. The easement is 10' wide easement and council engineer guesses it would be ~90cm diameter and ~38m long. We would redirect the easement along the side barrier (say 35m) and then frontage (say 15m) to allow us to build the duplex. The council engineer believes we would be able to reduce the width of the easement so it won't have a major impact on the width of the duplex. This is probably the biggest unknown to us as I have heard anything from 80-120K for this type of job.
- The land is flat but contains alot of trees. Five or six of them are 10-12m+ and I would assume we would need to remove most of them
- Haven't done a soil test/contour survey yet but contract indicated soil type is class 5 acid sulfate which is common in this area and many duplexes have started popping up. There is a bit of rock sticking out the back so it's possible that may add to the site costs
- Aiming for medium-high standard
Any helpful feedback would be greatly appreciated !
Spreadsheet is-
https://drive.google.com/file/d/1vlhLzh ... atOGf/view
Thanks