My experience was something like 5 appointments with Dr Harte for a diagnosis and 2 appointments with Dr Erasmus for a concurring opinion.
As for tests, I did a number of on-paper questionaires for depression, anxiety, dissociative personality disorder, and a rather essentialist questionaire on gender (seriously 1950s). I was asked a lot of questions, especially about my childhood.
I was already on hormones by the time I saw a Monash doctor, but it's possible they may also request baseline bloodtests (I had these when I went onto hormones).
I was asked if I would participate in a genetic study, where they are looking for genetic markers for transness, but this was not related to my diagnosis.