Need advice on my LiFePO4 build
So for context: I started out with a very janky setup of 4 EVE MB31’s using a JK BMS and AIMS power 12/1500 inverter. Use case is glamping with mini fridge, fans, air mattress pumps, coffee maker, etc.
I had wired it with stranded copper 2/0 which I think may have been overkill but was advised by an overly cautious electrician friend to be safe > sorry. Working with such thick wiring was absolutely miserable and I could not get anything to look even remotely neat.
Fast forward: I’ve obtained 4 more MB31 cells and had intended to run 24/1500 using 6awg but my partner has convinced me there is a good use case for keeping it 12v. His example is a 12v mini fridge, phone charging, 12v camping lights. Essentially avoiding the power loss of converting to AC. He also has a 12v solar panel already.
My hesitation: I already bought the 6awg wiring and connectors and I’m under the impression that if I do (2) 12v batteries in parallel that I will need a second BMS. He has 4awg that I can use but I’m worried that’s not thick enough for 1500w at 12v and I really don’t want to wire with 2awg or thicker.
My questions:
Is 4awg safe for 12/1500?
Would you spend 330$ on a 24/1500 victron and then 50$ on a 24 to 12 converter or buy another BMS, thicker wire, and thicker fittings?
Also any other advice is welcome. I don’t mind spending money for good future use cases. I also might want to power some home appliances in a power outage some day.
Pics of my current unfinished setup / components. I also have power switches and breakers not pictured.