To add to what Glen has said, (And I also hold an examiner rating) I have heard some in-house examiners are still only allowing the candidate an hour or so to prepare. This is not in accordance with the Flight Examiner's Handbook which requires 24 hours notice of the route, with some more details (weather, NOTAMs etc) with two hours notice.
It is important for all candidates to be familiar with the Flight Examiner's Handbook as that is the ONLY way a flight test may be conducted and anything outside of that should be brought to the attention of CASA.
Also a Part 141/142 organisation has to sign a certification that you have the required competencies for the test. Even if the flight test is in house - which I don't believe ANY flight test should be..
Some red flags to look out for.