I have a relatively big battery (12kWh) which is enough to see me through the evening during the summer months. We do not get quite enough sunshine where I live to be off-grid during the winter, but I can use the battery to hedge against grid outages which are common here in the winter due to storms (eg heavy ice taking down power lines).
Batteries have come down a lot in cost, at least the raw ones:
Without the tariffs it would be even cheaper I guess.
There seem to be a few sweet spots in solar - a tiny array that you use all of without having to grid tie it is really cost effective. (The cost of grid tied solar adds 5-10k to the system cost). Otherwise go big. :)
That and they can be cold booted and stand much more temperature diversity bitter and into frozen temps too.
Just saying, the tech and solar expansion is at run away global growth right now, despite American centric machinations.
Add a bit of extra capacity to the wind/solar installations and the battery figures usually plummet.
Then, subsides are drying up. Systems have a useful life, your panels can be damaged by storms, for maximizing battery life you need to ensure you don't discharge it below 20%, and neither charge it over 100%.
So, in the end, the grid needs to be there anyway, but as most grid costs are fixed, whenever you use it now, it is going to be more expensive.