Ballpark costs to retain and build - Perth

[Tulamalula]

I'm trying to get an understand of costs to develop a block with a house on it, ie retain and build. Hypothetically this would be in Perth, on a block big enough to build 2 x 2 x 1 units, approx 180sqm each behind an existing house.

For this exercise we're assuming the block is zoned appropriately.

What are the items I need to consider and how long would it take to

This is my very inadequate list of things to consider and it would be great if the more experienced than me (all of you could add to the list.

Purchase of said house and block
Stamp duty, transfer fees etc
Interest on purchase, and interest on extra to build the units
Plans
Site costs - eg soil tests
surveyor
Building costs
Cost of construction



See how little I know!!!

Thanks

 

[perthguy]

Add services to your list (water, power, sewer etc). A mate of mine just got a quote of $80,000 to create a new lot in his backyard (including services). IMO, this is unusually high but there were site specific issues including additional retaining, moving a retaining wall and drainage issues.