Hi @mdgolby
It all looks like pretty decent gear at pretty good prices to be honest. Bradford and Solargain are big national companies, I’m not sure about Koala and Synergy.
Honestly, I don’t the difference between the Q-CELLS Q.Peak DUO-G5 330Wp and Maxx 330W, I don’t understand why they sell such similar modules. If there is a difference it can’t be $2k worth. However, $5300 is quite a low price, and we generally wouldn’t suggest going for the lowest price. Huawei make good inverters too.
Regarding layout, I think the north and west roof approach that you’ve attached makes sense. Although the installers will need scaffolding or similar on the west roof for safety, that would be quite a drop (which could cost extra. One of those things that dodgy companies don’t break to you until they arrive on the day for install). Otherwise, can you use that flat north out the back and use tilt frames? Worth getting into the detail of that once you’ve established which company you want to work with.
Given the gear and pricing looks good across the board, I’d really just focus on the reviews of the companies in order to choose. If you don’t like the reviews of any of them, we do have a few other options on our Perth Solar Power page.
See also:
Good luck Matt. Let us know how you get on.
Cheers
Marty