No-one here can tell you if you will be refused entry on arrival: that is a matter for the border official to decide on the day.
You should check the entry requirements for your citizenship on the Australian Embassy website in your country. Google 'australia embassy' plus your country name. Make sure you look at the official embassy website, not at an agency websites.
You certainly do not have to carry a huge amount of cash with you, although you should make sure you have proof of sufficient funds to support yourself during your stay (bank statements and suchlike).