I went to Cairns in November. I stayed here
http://travellersoasis.com.au/ and loved it. As you can see, it is No.1 on the tripadvisor website. While most people are young, I have seen people of all ages. There is a common kitchen so you can cook. Anyway, there are also holiday apartments in Cairns if you do a search in Google. I want to move up there one day and hope I will finally have a garden so I can have a huge telescope.