Solar Panels: How many watts?

My daily use is around 100 ah. I have a "400" watt kit that so far has made a max of 300 watts during the hours when the sun is high in the sky. At that speed I need abour 8 hours of sun to fill my batteries from 50% state of charge to full. I have led lighting and I run my fridge on propane. I have a 430 ah battery bank and I live where it's sunny all the time. Two twelve volt batteries have less capacity than I have and your use might very well be more than mine. You can supplement with a generator as well and it depends on sun. I recommend getting the largest setup you can afford. The modest difference in price will pay off with longer battery life if you can keep your batteries at a higher state of charge and reduce discharge cycles.

My recommendation is to definitely buy the largest solar charge controller you can to give room for growth if you need more panels. I can add a fifth panel to mine, but if I buy more panels I may add three more and use series/parallel to ensure I don't exceed the 100 volt/40 amp rating. In theory I'm limited to 530 watts but solar panels won't ever make their full output without tilting and maybe not even then, so I've contemplated installing 600 watts of solar in that configuration to max my controller out as I doubt I'd exceed any of my other ratings under normal conditions.