Batteries for backup only

I live in Ohio and am getting solar panels installed soon. I’ve been considering adding batteries because we occasionally have prolonged power outages (maybe once a year or a little less frequently but sometimes for as long as a week).

Anyway, it seems that batteries and an automatic transfer switch would be the best solution but the quote I got tacks on about $14k to get an Enphase 5P or $19k for 2x 5P units.

I would definitely get a Span panel if I only got 1 battery just to help dynamically kill circuits to keep under ~4kW / 5kWh of consumption while the grid is down. I could probably live without the span if getting 2x batteries as I think they could work as a whole-home system.

I know I’ll kick myself the next time we have a power outage and I can’t use my solar panels at all. But I’m wondering if there are some more cost effective options to consider? Going with the 5P system could nearly double the total cost of the setup.

Anyone been in this position? Since we have a 1:1 credit system, the batteries really aren’t necessary unless the grid is down. But I really like the idea of using my solar panels while we have an outage. I can’t really find any other ways to leverage the panels and IQ8+ mirco-inverters other than getting a system controller to tie into one of a few battery options.