Thank you very much for your help with my questions. I went ahead and ordered the battery, panels, and inverter.

Is this product the 'smart shunt' you were referring to? Looks like it has two pieces? I also bought a Samlex remote for my inverter, but that's slightly different right?

As far as circuit breakers go, you said they should be 'UL approved'. I found this BlueSea breaker on Amazon, which gets good reviews, but isn't UL approved. Is there a particular brand you like for UL approved breakers?