The amount of money you bring with you is a personal decision; however, you must make sure you have enough funds to cover your bond/rent and moving-in expenses for your accommodation on arrival. You should also have money to cover temporary accommodation expenses (hotel) if applicable, meal costs, and transport costs (buses, taxis).
Generally, it is advisable to have easy access to AUD$2500 to cover moving expenses and AUD$800 in traveler's cheques or Australian currency to cover incidental expenses such as hotel, meals, and transport for your first few days in Perth. You should not bring large amounts of cash with you – please ensure you bring the bulk of your funds in traveler’s cheques or as a bank draft or money order.