If you want to buy real estate and you are the holder of a temporary visa first you need permission from the authorities. Generally, people with temporary visas can only acquire new residential property. They can also buy a second-hand dwelling as long as they use it as their main residence and sell it again after they leave Australia (unless buying it together with their Australian spouse).
Any proposed purchase of urban real estate, farms or rural residential blocks must be approved by the FIRB (Foreign Investment Review Board).
Permanent residence holders have no restriction. More information will be found on www.firb.gov.au