I recently got a chance to listen to the pitch of Ion Solar, and if you don't fact check anything that they say, its sounds pretty good. Here are some of those statements, fact-checked:
"Solar will add between 20-40% to the equity of your home."
This is the silliest thing I've ever heard. Not even Zillow, with their 100% larger error rate than they report, pitches this kind of nonsense. Zillow reports a 4% increase in home value (which is highly dependent on the region) and not evidenced anywhere in the Richmond VA area.
"Solar panels last 30-50 years," and "we'll replace them if they drop below 85% efficiency within 25 years."
I was quoted the SIL-380 panel. This panel's manufacturer rates its performance at 85.1% in the 25th year. See a problem here? Ion believes that below 85% is too low, but is fine to let you believe the product will last another 25 years beyond this.
"Electric prices will rise, conservatively, 4% per year."
This would constitute an unprecidented rise in prices well above the last 20-year average.
The fact remains that your solar array will need to be replaced every 20-25 years, while causing penetration points for your roof, and having a diminishing return over the course of their lifetime. If solar reaches half the cost it is currently OR the price of power doubles, there may be a case for solar economically, but for now, it remains an environmental argument. There is a reason that solar still requires enormous subsidies... its because the math doesn't work for consumers. Maybe installers can make a killing, but buyer beware.