Well, yep, that’s pretty much what I wanted to do. Company quoted a 3kW array with no battery for about ¥1.3M and with a battery for ¥3.3M. I ask about them adding the cables to the battery and I’ll add the battery later. Apparently the no-battery system meant a no-battery inverter. So I asked about adding the inverter from the with-battery system. Sure, but that’s an extra ¥100K. And, oh, no guarantee on system performance with user supplied battery.
What could be ‘special’ about their inverter, or their battery?