In order to begin work, you need to apply for an Inquiry Agent Licence from Consumer Affairs and Fair Trading after you have completed the appropriate course. You must provide a National Police Check and be at least 18 years old to apply for a licence. Visit their website for more information.
You will need to obtain a Certificate III in Investigative Services
“The Certificate III in Investigative Services offers the skills and knowledge required to plan and conduct investigations, co-ordinate investigative work teams, undertake surveillance or factual investigation, and apply the legal requirements of private investigation to your practical work”.