I would be very suspicious around claims from people trying to sell you solar panels. There are a lot of incentives in the US such as tax credits. This is good but a lot of people in green energy industry include that into calculations, which is fine except its under the assumption that the incentive will persist. Even Tesla shows you "net effective" price of their car by calculating the gas savings (e.g. Model 3 purchase price is 47k but they "potential savings" price is 38k which include potential incentives and gas savings of $8,600)

There are other gotchas like PACE loans being senior to your mortgage. So if you get a PACE loan, the loan is transferred to the person buying the home and is senior to your mortgage.

I'm also suspicious around the maintenance and longevity claims. For instance, from my experience, the energy efficient light bulbs do not live up to to their claims. I changed about half of my lightbulbs within three years and they supposedly have a 20+ year lifespan. It's fine that they don't have a crazy lifespan, but it just shows the industry is okay with outright false claims.

Overall I think the industry is so juiced by incentives and manipulated by regulations that it attracts shady players.