Those prices for trades are not far off, i just finished a build and the big issue is productivity. The australian tradies do f*** all for what you are paying them and if working on day rates, alternatively youll be hit with a huge fixed quote for job if going that way. They are packing their tools at 2pm and don't even start until 7:30, absolute joke. This prolongs the job and holding costs for the developer.
What needs to happen is to loosen the visas for trades and then you will see productivity improve when supply of labour is increased and the builders and clients gain the upper hand. The chinese guys work until 6pm and also Sat/Sun, i use them wherever i can, great work ethic.