I too am driving down in my VW Golf 1.9 diesel. Just over 1/2 tank to get down n back
I have not locked my date in for going down just yet, but it will most likely be the 27th. I am staying down until the 11th April.
Bikes go on the roof, gear in the boot. Room for 1-2 more people.
Your costs fuel and portion of the long term parking. My car averages $6 per 100km's