One consideration when thinking about taking the furniture. Our container took months to arrive and clear customs, so we still had to buy/ rent furniture, fridge, washing-machine, bed, mattress, chairs, sheets, towels, ... you name it. and the restrictions about bio-safety are a true madness, so for two years, I wouldn't really bother. Just take clothes and buy the basics at Ikea, K-Mart. The only thing I would bring are nice wool blankets which are impossible to find and be prepared winter can be very bitter and cold. Last year was shocking, so far this year we are on the opposite side, and having the warmest autumn recorded in years.
In our package, house is paid for two years, school is paid as long as we are on the 457, health insurance is paid, one trip home per year for the whole family, car allowance and as much container space we needed.
We have been here almost two years, now, and Sydney is way more expensive than I expected, even after being told it was expensive. Eating out, cinema, even the kid's activities, hairdresser ($$$$$).
Rent vary enormously from suburb to suburb. Do you have an idea where you will be living/ working? Where we are, rent for a normal house without pool is $1100 per week.
Unless you are near a train line or the CBD, public transport is useless, so you will need two cars. Used cars are far more expensive than Europe, and in NSW registration is around 500$ /year and you also need what is called green slip which is a kind of second insurance ($500) on top of your insurance ($500), so consider around $1500/year just to allow your car on the street.