I don't know if the market has improved but when I looked at this a year or two ago I concluded that the consumer market here was utter crap with hugely inflated prices.

The cheapest per kwh way I could find to buy a home battery (that didn't involve diy stuff) was to literally buy an EV car with an inverter... by a factor of at least two... I ended up not buying one.

Unfortunately cheap batteries doesn't translate to reputable companies packaging them in cheap high quality packages for consumers instantly.