You should be able to learn about various financing options like leasing from local solar panel installers.
However, I feel like you're probably looking to own the panels, so leasing might not be an option.
San Francisco has a municipal electric utility, and they're still offering solar rebates. While incentives in other utilities are winding down from the California Solar Iniative, San Francisco's will most likely stick around for longer. You can learn the latest about incentives on their website.
Other incentives include the federal Investment Tax Credit, which is worth 30% of your total installation costs.
You could also look into what kinds of solar panels each installer is offering. There are certainly pricing differences between equipment, so be sure to ask what the makes, models, and sizes of solar panels they install are. If you don't mind sacrificing some quality, you could choose more affordable panels.