Settlement agents in Perth like to see you face to face before opening a file. Positive identification is important to settlement agents to minimise their risk. After all they put their settlement agents' license at risk, large amounts of money and their reputation at risk. Settlement agents also like to see important ORIGINAL documents such as land title deeds. Yes you can insure they're posted safely but you might feel more secure delivering them personally to a settlement agent near you and at the same time bringing your ORIGINAL proof of identity documents such as passports, birth certificates and or marriage certificate.
If you're far away from a settlement agent's office in Perth such as in a remote Western Australian town or overseas and you can't make a personal visit to a settlement agent's office in Perth, then proof of identity documents and contract documents signature witnessing need to be done by notary services at an Australia Post Office or Australian embassy / consular office.