Fortunately for you, Los Angeles has a lot of sun, and those cameras don't pull 1A continuously, actually far below.

You just need to add a battery, and then a couple (automotive) 12v to USB plugs.

As for the math, if you turn the IR off they consume 2 watts, so that's 12 watts total for your 6 cameras. You only need 1.5 sun hours per day to produce that much with 200w of panels, which will be easy in LA even in winter.

So the only question is battery size to make it through the nights. I would aim for about 200wh of usable storage, or 300wh would be excellent. With lead-acid you should only use 1/2 the storage, so you would want a 50ah 12v battery (300wh usable) like THIS. With lithium you can use more of the storage so you could go with around a 30ah 12v lithium (I don't know this brand, but something like THIS).

If you want to use the IR at night, 200w panels will still be plenty, but double your battery needs. 80-100ah of lead acid, or 50-60ah of lifepo4.