On arrival to Thailand, you need to register your address with Pattaya Immigration within 24 to 36 hours, in soi 5 Jomtien. To do that you need your rental agreement, copies of your passport and pages, fill out the form. Once you get the TM30 receipt, you apply for a residence cert which costs 300 baht. You can use the resident cert to get a licence (with a medical cert), buy a vehicle and open a bank account. It is valid for 30 days. If you intend to be a NON resident of Australia for tax purposes, you should visit a good accountant and get them to notify the ATO on your behalf that you will be leaving Oz and a non resident. You must also be paid from outside of Australia and it is recommended to be into a foreign account. It also helps to rent out any property in Oz, not have any bills in your name, and even sell vehicles if you want to legit.