Solar is typically quoted as $ / Watt.

For reference what you quoted was 0.7 $/Watt not 7 cents.

While the cost of the panels has dropped - you still have balance of system and, yes, the unbelievably high interconnection costs (location dependent)

I totally agree and fixed it in the post you responded to. At the end of the day a panels and electronics are a minor contribution to the project cost.

I think in most of California it is still legal to do home electrical work, provided it is permitted and inspected, but I'm not sure if this is true for solar as well.