Congrats man...I was lucky enough to get a single room @ 80 AUD per week, It was in Coffs Harbour back in 2009. Room size is about 12 ft by 14 ft but with shared bathroom and common kitchen. I wonder if such rate can be available in any suburb of Sydney, like Lakemba or Bankstown.
I am also planning my visit around March 2017, either in Sydney or Melbourne. Not finalized yet.
Can you please provide some guidance regarding home search.