Its easy if you're interested in and good at Com.
I'm in the process of transferring to Eco (Sco Sci)/Law at Sydney and I've been told that an NSRL cutoff of about 96.15 has applied since 2001. That means you need a D average and a UAI of at least 96.3. But it is a competitive and the selection rank varies depending on how good the other applicants are.
See Frigid's transfer FAQ - is good.