Sunrun review: Solar panel installation

I reached out to Sunrun regarding providing information on an application that would fit my needs. My neighbor was a newer and a happy customer and recommended the company. After meeting, we had a plan that I was ok with, and we moved forward. I was told at that time that I would be non-dependent on the grid. Installation was great with no issues. No one ever discussed battery back up at that time. Post installation and right after I was starting to use my panels, I inquired on a battery backup and was told my system could not work with it. Coincidentally, I received an electric bill of $106 over and above my solar payment of $110ish at the same time. I was very upset with this. I inquired about why this was happening and was told my system was too small. I asked about adding additional panels and after reviewing that option, was told no more could be fit on my roof. My neighbor, also a Sunrun customer and who has more panels than I do has the exact same roof size. I asked why can he have more panels than I do but I can't add any since we have identical spaced roofs? No one could/would answer my question. So