there's a 4x4 hire place here and [url=http://www.ozhorizons.com.au/qld/fc/bay/bay4wd.htm]here[/url.
But you won't need a 4wd for brisbane itself, and thier too expensive to have for the time you're here.

[url=http://babs.com.au/glasshouse/]this looks like a good place to stay on the way to Fraser if you like.