BEWARE OF UNINTENDED MISINFORMATION ON HERE FOLKS.
"If you wish to maintain your own aircraft, whether you built it or not, you do the SAAA MPC Course, qualify and take your certificate to CASA, who will give you a certificate to maintain your own aircraft, under their requirements."
Sorry Burnie - you obviously don't know how it all works. I'm sure your info was well intentioned though, but it's not accurate.
CASA Instrument 18/22 (in part) allows builder of a VH registered amateur built experimental aircraft the entitlement to maintain the aircraft they built, if they do a course of training on regulatory matters, such as the SAAA MPC.
SAAA MPC certificate is not in itself an approval to do anything, it's just a certificate of course completion.
CASA gives nobody personally a certificate to do anything. It's not true.
Also, amateur-built experimental aircraft must obtain an Experimental Certificate, not just CASA registration, pilot must have a CASA pilot licence and a CASA medical - such as Class 5. Switching an RAAus plane to VH-EXP is not a five minute job and there are a lot of other factors at play, lots of ducks to be put into lines before pulling the trigger on any of it.