I would always be suspicious of any company going door-to-door selling something very expensive regardless of the product. I have seen other article online where renting/leasing solar can be a HUGE issue if you ever try to sell your house. If you are serious about installing solar, I would suggest YOU be the one to make the initial contact, get at least 3 estimates and compare notes with friends/neighbors/etc. who have installed that type of equipment so you understand ALL of the costs. Companies trying to sell you solar will likely play up the BENEFITS but make less effort to inform you about the ISSUES/DRAWBACKS/CONCERNS. For example, in some areas your local electric company will buy back your excess electricity BUT at a much LOWER rate than they sell it to you.
With all of the complexities, make sure to thoroughly investigate how it works in your area and don't jump into anything. The math on the cost effectiveness of solar depends on where you live, how large of a system you install and factors like the price to sell to your local utility. In some parts of the country it makes sense, in other places not so much. If the economics don't work out, you are simply pre-paying your future electric bill and not getting much if any benefit. Panel output degrades over time and they eventually need to be replaced. How much of a payback you think is reasonable will have a significant impact on that calculation.
We looked into installing solar when building a new home in a different part of the country a few years ago. The math didn't work out and the payback was long enough that the panels would probably need replacing about the same time we broke even on the initial cost, so we decided against it.