While you are Not My Engineer and <disclaimers> .. are there any bloggers / vloggers that are or at least seem to be giving good advice that you are comfortable passing on?
Yes, there is an Australian dude that has pretty much seen it all, and he's paid his tuition fees so he's a lot more careful now.
I'll look up his name tomorrow, it's been years since I last looked at that (it's 5 am after a night of hacking so I'm off to bed).
Found it:
https://www.youtube.com/c/HBPowerwall
I like the simplicity, I don't like some of the wiring choices but I'm not sure if that is to be code compliant in Australia. Enjoy!