We had 18x510w panels (9.2kw), 2xZappi chargers, PW3 & Eddi (to heat hotwater) installed ~5 weeks ago. Total cost was £17k (inc. scaffolding, cert, etc), in the SE England, with a small recommended contractor. The UK solar market is full of rogues as well, charging massive sums, many for pretty questionable systems. We had 5 quotes to get there, 3 of which were crazy in one way or another.

We hit our first MW/h of power today. In England. In April. Total electricity bill for the last 6 weeks is about £30, and that includes our driving (previously £150 to £200 p/m) and most of our hot water. If you have the property for it and available investment, the ongoing savings are instant and obvious! My instant regret was not having done it sooner. Driving around on your own sunshine does feel magical as well!