No. Western Australia has no cooling off period for real estate contracts, so once the seller accepts your offer and the contract is signed by all parties it is legally binding.

If you want a way out, it must be written into the contract as a condition before you sign. Buying off the plan works differently, because a buyer of an off the plan strata lot has limited rights to avoid the contract in some circumstances.

See There is no cooling off period for real estate contracts in WA and Buying off the plan in WA.