German Car Zone

The guy called just then, engine oil+filter change, brake fluid change, total $937 AUD, or $ 674 USD

Wow ~$500 for a brake fluid flush. If you get it done, make sure they actually do it and not the suck and fill of the reservior.

They said they are going to flush the system. They are doing it now, going to pick it up in an hour or so. What else do I have to look for, I specifically told them not to change the air con filters, and not to top up the washer fluid. The guy said the washer fluid is necessary because it lubricate the wipers and prevent bacteria from building up inside the bottle. I still refused his offer.

Labor cost is probably going to be the most expensive thing.

Yes they said "they will flush the system". Many will "flush" the system by just changing out the fluid in the reservior. On normal brake systems this is done a lot when part of a service, if it has its own line for a brake flush then more perform the service. SBC is a pain and no one likes to to anything to the system. Hopefully it is a slow day and they have nothing else to do.
The first person to do SBC brakes in my first shop, it took him more time to bleed the brakes then it took him to replace front and rear pads and rotors. And he even gave up after a while. But the system to bleed the brakes has improved a lot over the past six years. So now it is now just a PITA instead of complete PITA

You can do filters and washer fluid easy enough yourself.