What if you have car trouble along the way. you would need to have a bit of cash for that. overheating, getting a flat, hitting a kangaroo.....Id fly for sure. its cheaper and someone else said sell the car to help you move, then you save yourself $1600 and make some cash too. im sure the busses are ok in melb untill you can afford to get a new car!!
Dont be ashamed to take the 'easiest' option....none are really easy! good luck with the move!