yes you can stay at St Andrews or Sancta.. i know Wesley and Womens don't accept people from UTS not too sure about Pauls or Johns but i don't think they do either
You can stay at some of the uSyd colleges. You should also apply for UTS Housing because competition to get in to the USyd colleges is tough and you may not get a place, and you don't want to be homeless. UTS Housing is at www.housing.uts.edu.au
Gumal Ngurang is the best UTS residence, followed by Bulga, then Geegal... based on new-ness, social life, comfort, location etc. Blackfriars is crap and is only for postgraduates.