When I got solar several years ago I watched as the various installers wasted a ton of time selling to me. It was clear that all the steps between when I was interested and when I gave the go ahead to start the install were extremely expensive in the big picture and in the long term the winners of residential installation would be those that will be able to drive that cost down and or spread that cost out to as many customers as possible.

They visited my house when I was just looking for a quote. The quotes were these large custom contracts with all the information which we would iterate a few times on.

I can imaging these days just going to a website, finding my roof, selection my option and getting a quote in real time. Maybe they would even let different installers all bid for the job, who knows. The website would have detailed information and information if I want it. Only if I did an initial downpayment would someone come out to confirm it could be installed. Someone like this could be able to drive the install cost down.

Or maybe "groupon deals" where if you and 4 other neighbors on your block all buy solar it is 15% cheaper or something. That would be one way to shift the marketing and sales to the consumer and not the installer.