@aicee
I agree with @maguero, you can get a Proof of Age card (also called Photo Card in NSW) since you're still living in Sydney. That was one of the very first things I did after arriving in Australia, para hindi kailangan bitbitin ang passport everywhere I go. Pagkalipat nyo sa Canberra, try to get an ACT Proof of Identity card and ACT driver's license para additional ID.
Offering to pay the rent 6-12 months in advance is not advisable (it sounds dodgy, even). It's a big financial risk to anyone, kaya fortnightly ang bayad ng rent in Australia. Landlords or property agents generally look at employment talaga (they look at whether you have a stable job and source of income) and rental history. I'd say try looking for short-term/temporary accommodation in Canberra via Flatmates.com.au, maybe at least 3 months. Minsan kasi less strict ang mga potential landlord or flatmates na nag-aadvertise dun since hindi ka kasama sa lease contract, so that's a good way to start. And then after a few months, once you've secured a stable job in ACT, you can ask your current landlord and/or supervisor to be your referees when applying for a rental.
Most real estate agents will call your referees to verify your character, your behavior towards rental properties (like if you keep the property clean and organized), your history of paying rent on time, and your capacity to pay.
NSW Photo Card: [https://service.nsw.gov.au/transaction/apply-nsw-photo-card](https://service.nsw.gov.au/transaction/apply-nsw-photo-card)
ACT Proof of Identity: [https://accesscanberra.act.gov.au/s/article/proof-of-identity-cards-tab-overview](https://accesscanberra.act.gov.au/s/article/proof-of-identity-cards-tab-overview)