Well, here, France, LFP batteries now cost MUCH MORE than just three years ago (final customer price) and... ~1000€ per kWh, while just 3 years ago they was a bit less than 700€ per kWh, the battery alone (with BMS etc) but we also need an inverter witch as well is not much more expensive and I talk about self-assembled systems, here legal, but not legal in large slice of the EU, because retail price of a complete installed system by some p.v. companies are so high that there is no economical reason to install them.

My system is 5kWp/8kWh @11.500€ three years ago, it would be now a bit different (400V batteries instead of 48V and a hybrid inverter instead of a p.v. string inverter AC coupled with a battery inverter) @~ the same price due to a single inverter and slightly cheaper p.v. modules (@~100€ for a 415Wp). If done by third parties the cheapest proposal back than was ~30.000€. At this prices given current electricity prices and local grid stability it's a nonsense, it's even cheaper a diesel generator.

I know prices in China are FAR lowers, and I've read also on far lower Thailand prices, but compared to local cost of life I can't quantify how much.