30kw DIY battery for $310/kwh, which hybrid inverter is recommended?

[oregon_phil]

The Sunny Island split phase option can manage a generator. This is their off grid solution, but as far as I can tell, doesn't work with the SMA automatic transfer switch but will manage a third party transfer switch between the grid and generator. I didn't elaborate earlier because this is an expensive solution. But user Salts bought some sunny islands cheap and did the work himself to it turned out to be a nice system.

[khanh dam]

well youtubers are showing off their 272ah lifepo4 batteries now. much better price of about $120/kwh of storage.

https://www.youtube.com/watch?v=j7ocFLUO_qo

[Ampster]

well youtubers are showing off their 272ah lifepo4 batteries now.

Yes, lots of people on another forum have developed reliable sources for those 272's, and some 280 cells from EVE.
Did this thread discussion about surge loads inform you about the complexity of picking the right hybrid inverter? It really has nothing to do with the kWhr capacity of the batteries except the batteries need to be able to provide the kW discharge to serve the loads.
I was able to open that video after several tries. I have used that same vendor ( Emily at Shenzen Basen) before with good results. Search for Shenzen Basen to see more reviews.