What about drilling holes in your roof?
The solar panels are mounted on a racking system that is bolted to the roof of our house. The bolts go directly into the rafters of the roof, so they do not actually create a hole in the roof of the house that would leak into the attic.
We have close up pictures of our racking system in our photo gallery.
If you or your installer is considering an alternative mounting method that would fit more panels on your roof, DON’T! Keep the racks in position over the rafters, and live with whatever size system that will accommodate. If your installer is being pushy about this, then find another installer, quick!