ECO-WORTHY 5120Wh SL3500 Stackable Power Station with 20ms UPS,Solar Inverter AC 3500W Output(Surge 6000W),Expandable to 15.36KWH,LiFePO4 Battery with BMS,Portable Stand for Home Backup,Emergency

I for one think you have a very well thought out system. I see that everyone is trying to be helpful with alternate suggestions but if your setup is really only $1200 then you are doing great. I did want to suggest this https://a.co/d/0c9BzNZY But I see you already have seen it and have reservations over less capacity and the all in one nature of the electronics.