Gotcha. Sounds like an off grid 2-4 Kwh system with batteries – ish.
All solar components have improved in efficiency and come down in price over the last few years. With the exception of batteries. No earth shattering leaps there yet. AGM batteries will be the way to go, I’m sure.
Forget a power wall at the moment. Can’t get it and no follow on support/repair components available right now, or maybe ever.
As far as subsidies. A lot or conventional power companies are making it so it’s not cost effective for solar, or you can’t do it at all for grid tied. So you may get a nice subsidy on the front end and much higher cost on the back end. E.G., gotta pay extra for the “use” of the grid, specialized metering equipment, higher monthly base bill, etc.
Couple more questions. Is this a DIY or pay somebody to do it all or in part? How’s your local power co. with solar, do they pay, charge or nuetral?
If you’re a pretty decent DIY’er you could design and build the system as I’ve described above and save a few hundred $ mininmum. If not or you want grid tie, you might want to pay a bit extra for them to do the more technical aspects.