Having lived here for a year, you need to be aware that buying clothes, books, shoes and food at supermarkets is more expensive than the UK and customer service in supermarkets and banks is shocking. Australia does a good job in giving the impression it's cheap - trust me, it's not.
Updates
Send your feedback or queries to been.there@guardian.co.uk
Search Been there
Books are quite expensive (insert joke about illiterate natives here) but otherwise I'd say most things are 10-20% cheaper than home. Eating out is about half the price and generally streets better. And, with a few exceptions, customer service is noticeably more upbeat and friendly.