I actually used to work in a solar & heat pump company.
YES it does attract a huge amount of scummy people on both sides.
Some comments have already answered on the side of sales, but it also attracts a lot of shitty clients.
How? A lot of people get greedy with free energy and/or homesteading/offgird wackos. Usually they're unable to pay the "normal" price so they chase down such scammy companies because the number they have offered fits their budget.
IMHO definitely an industry to avoid working in.
I'm actually having a shower, just being too tired/unmotivated to do it at "normal" speed.