A couple of thoughts.

If you are going to use lead-acid batteries for your power backup, look for 'deep cycle' batteries that won't be damaged when you inevitably discharge them below 30% (hey, it happens) - and be aware that lead acid batteries produce hydrogen, which can be explosive.

Inverters are not at all efficient. Converting 12VDC storage to 115VAC power means a good bit of that is going to be lost as heat. Run as many things on 12VDC as you can. For instance, look at for-car power supplies for your laptop.

I know this won't be popular with the global warming set (and they're not wrong) but if you're on a gas line, look at generators that can run on natural gas - better yet, look at fuel cells. Compared to generators they are quieter and produce less CO2 per WattHour generated, and they're pretty quiet.

Either way, use a transfer switch to make absolutely SURE you are not feeding power back into the grid (you'd be wasting power and might hurt an electrical serviceperson - and they are our FRIENDS).

Finally: did you know that there are refrigerators that run on propane or kerosene? Our camp in Maine originally had one (grid didn't reach that far). Worth thinking about if you're going to be days without power.

I'm in New England. We get power outages, too, but it usually happens in the winter (blizzards / ice storms make trees fall on the wires). Staying warm, and keeping pipes in house from freezing are issues, keeping food cold is not.