If you rent a 1 bedroom apartment, it costs about 400aud (per week)?  I suppose 4.5K should be enough if you are single. You should be able to save if you spend cautiously. Living expense in Sydney is the highest in AU. Working in Sydney will be interesting, it will be like another 'KL' city, though I have not worked in Sydney before. 

Dear malaysian in melbourne, where is the best place to count down?

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Added on December 27, 2012, 6:03 pm

My ideal place is somewhere nearby Alberk Park or South Melbourne, so that I can go to the MSAC stadium anytime that I want. I am a bit picky, prefer to live in a house with a garden, which I think it is a bit hard to find in those area. I don't mind sharing. The current place that I live is 7km away from the city. Hence it is a bit hassle for me to travel especially after a late night sport session. I am happy to live in the current place,  in fact I am living with an aussie landlord. The experience is terrific. Tough decision, to move or to stay.

I was in sydney before. Which suburb are you allocate to? At least i could recommend you some of the places.
I think you should stay near to your workplace, which around 10km radius.
Since you're saying the workplace is a suburb, i think you can get yourself a car which is very cheap there.
Sydney is like KL, sometimes there's traffic everywhere (of course not as serious as KL).

http://www.realestate.com.au will give you an idea of how much you'll pay for rent depending on where you are.

http://www.coles.com.au/Shop-Online.aspx will give you an idea of what you need to pay for groceries etc.

http://www.131500.com.au/ is Sydney's public transport info to find out monthly pass prices, how long it takes to go from your work to home etc.

Sydney is expensive, do a bit of homework because only you know what you spend every month and what you consider to be a minimum.

If 80k including allowances and super, you're generally looking at 4 or less cash in hand (realistically 3.8).

As you're given a company car remember you can't claim for tax deduction.

Your ability to save will depend on how much you spend on rent. Inner city parking is so insane these day I usually just ride my motocycle. My advice is to find out where you will be based out of and check the rent and gauge your cost of transport. I easily spend up to 400~500 dollars per month on just fuel. That's just regular travel.

Also like some others have mentioned, you will need medical insurance. This is a condition of your visa. For a decent level of cover you're looking at 1200 dollars. If you want the best level of cover (trust me a hospital visit here is 780 dollars easy), that's 3000 a year.

Well, I think this a good start for yourself. As mentioned by others, your medical coverage is far way important.
80k won't make you rich but think about the future. You'd have extensive working experience prospect in your résumé in future. As long your salary could cover most of your expenses, i think your progression to higher level is expected.

Newington is near Homebush, which is quite near to Olympic park. Plenty of public transport. I think you can easily settle down. Plenty of malls and groceries store around.

I suggest you to find a place near parramatta,ryde, rydalmere, ermington or rosehill which is quite close since you have a car

rhodes, silverwater is near but freakin expensive unless you know the houseowners thre

pm me if you do need some property rental agent as i can hook some up for you but pls do your own research whreabouts you wanna stay

I agree. now i feel like swimming in the ocean try to grab anything for survival.
HAve to compete internationally and a little bit of luck. It aint easy, if no choice, look for casual work 1st. at least could pay my bills and rent.
Nursing is always in highest demand. I remember a lady from thailand i knew she earn big salary there.