How to get screwed with solar. The VAST majority of door to door solar sales have a priority to get you to sign on the line for a loan. They don't give a damn about production or shade. They will show you the modeled production without accounting for shade issues.

Warning signs:

1)salesman wants to talk about how much he can reduce your bill instead of kWh. This is the equivalent of a car salesman discussing monthly payments instead of the actual price of the car.
2)They do not use their own install crew. They will sub the job out. This means that when the crew shows up, their incentive is to get those panels on the roof and get down the road. I've heard horror stories about the salesman sold a number of panels and all won't fit due to roof easement requirements, so the installers will put them in another place. Keep in mind, the installers are paid for the job and don't give a damn about the install.
2a)if there's a roof leak, the solar company will tell you to call the installer. But you didn't contract the installer or even pay him so he won't respond to you.
3)The sales place will set you up with two loans. There will be a short term 0% apr loan for 18 months for the portion of your system that applies to hte tax credit. But if you can't claim the entire tax credit in one year, you gotta roll the tax over. But the loan will revert to 30% interest from day 0 if you don't pay if off in 18 months.
3a)The balance of hte system will be put on a 20 year loan and a lien will be placed on your house. When you sell your house, that loan will be satisified out of the equity in your home. There is no obligation of teh buyer to take on that loan.