I just looked at our pay scales and a year 4 SO gets $71000 AUD plus maybe another $10000 in hourly pay.
He is an expat so he gets a small housing allowance to allow him to buy/rent a
small flat.
As far as I know Australian airlines don't pay housing allowance to allow you to buy your own house.
And sorry, how much tax does your mate pay? Maybe 15% and that's it. No medicare levies, flood levies, etc.