Hi Mimmy,
It seems that need to cost several thousand AUD to import your car to Aus, because the safty standard is different for hong kong and Aus. Some people will just simply sell the car in hong kong and buy a new one in Aus.
For me, I will definitely import my car because of some reason. Therefore I did some research about how to import my car to Aus.
Below is some useful link for your reference. As I never do it before, so my understanding may not be correct.
8 steps to import a vehicle
https://infrastructure.gov.au/vehicles/imports/process_overview.aspx
Agent that help you to import your car(There are many agent do this business)
http://www.bespokeinc.com.au/index.php/compliance
Second hand car price reference
http://www.carsales.com.au/
Aus Forum about importing your car
http://www.pomsinoz.com/forum/transport-shipping/97053-transporting-your-car-oz-everything-you-need-know.html
I'm thinking of bringing my car to oz too. There are two ways: RORO (rolls on rolls out) which is cheaper or to put it in a container together with other stuffs.
I'm having the moving companies to quote by combining the car and the furnitures in a container
Some reason that you will import your car to OZ
1. Your car is your dream car and you want to own it for a long time no matter where you go
2. Your car model do not sold in OZ
3. You want to import a special car that is very rare in OZ to make money