I've been putting off even requesting quotes for years, but this thread got me thinking about it again. I ended up finding a site called energysage.com that seemed trustworthy enough. They anonymize RFQs for solar installs and send them to contractors that they've vetted. I entered my info last night and got two quotes back today. Turns out rooftop solar probably isn't a good choice for my house. Payback would take 12.5 years, half of the equipment warranty. That's if I pay for it all upfront, much longer if I get a loan. The problem seems to be that there are two big maples in front of my neighbor's house that are shading a lot of the South facing part of my roof. Oh well!