Pricing for solar panels is quite complex. The price will mostly involve:

- The state of the roof (does it need reinforcing? will the installers need scaffolding?) - The complexity of the installation (lots of little roof sections with earth tiles and 2 or 3 transformers? Or a plain and simple one-transformer south facing asphalt roof?) - Does the crew need to drive 5h from headquarters? Or just 1h? - A 3kW installation may be worthwhile in some locations but not in others.

And finally since solar city depends on the performance of the panels (which they sell as debt), they must ensure that your house will be a good candidate. If it's not, they don't want you as a customer.

I imagine that's because there are more variables with a solar installation than with a car that has clearly defined options.