more than double what it would cost at market rate
I definitely paid more for labor than for materials. My payoff time is about 13 years with a Tesla Powerwall 3, maybe a bit less now that I have an EV. I had a team of 4 guys plus an electrician here for about five days.
I did go with a slightly more reputable company that charged slightly more, but I would have gone elsewhere if it was a huge difference.
Maybe I should get around to making a post in !Solarpunk@slrpnk.net or something, even though it isn't very punk.