Its illegal to have a VHF radio on your boat and not have someone licensed aboard to use it.
15 minutes is all it takes most people to sit the theory Multiple choice exam to get their license. There is no practical test. All you need to do is study the theory, book the test with one of Perth Boat Schools invigilators, then do the test.
Cost of the Study Book is $25 and to do the exam with Perth Boat School is $60. Then there is a fee you need to pay to the Office of Maritime Communications for them to process your exam and if you pass, issue you the license.