I did this in inner sydney (ultimo, pyrmont) for about three years, although I rented large top floor units with 3 bed rooms and rented the rooms out for $440 each to couples. My wife and I payed around $60 rent in total for years.
I did get lucky with cheap rents though.
Then the rents increased too much when the landlords realised how much they could get.
It ended up being too hard so I just rented a small place. It's not worth it anymore, too much of a headache.
How did you report the income in your tax return?