Insurance

The answer, of course, is NRMA Insurance! Their premium was very competitive for my EV.

Too many variables to give a definitive answer to that question.
Full car specs, driver's age, driving history, claims history, "loyalty" discounts based on number of policies and time with company, postcode, etc.
Unfortunately, you will have to do the hard slog to find out which policy is best for you.
The only thing I would emphasise is the cheapest one is not always the best one when it comes to the unfortunate time if you have to make a claim. Go with one you think will give you good service if/when you need them.