Going Rates for Solar in San Diego

In 2015 I paid $2.70 per watt (pre-tax credit), so you should be able to do better. I got quotes from Baker and Sullivan as well, but they were higher. I went with https://solareenergy.com. They did an excellent job. I've had no problems since with the system or the roof.

I've got no experience with Energysage, but Palomar has installed several systems in my HOA and seem to install fit for purpose systems. I don't know the owner but he lives near me.
Baker has been around for well over 10 years. When I was doing my system design and getting quotes, they were one of 3 vendors I was considering as the 3 best IMO as the guy in my HOA who reviews/recommends all solar and PV work for approval to the HOA. At the time, baker was my choice of vendor to beat based on their quality. The other 2 vendors were Sullivan and Milholland, both of which have several installs in my HOA I was quite familiar (and impressed) with.

In spite of, or maybe because of their high quality work as I observed it close up and during installs, Baker wouldn't negotiate on price. Sullivan would negotiate some but wanted some PV modeling software I'd written that they'd seen around my neighborhood that I had shared with neighbors. I declined to do that so they withdrew after the first round of bidding. And, their initial prices were not quite competitive with either Baker or Milholland anyway. Good quality work but the price and attitude were not suitable to my needs.

This sounds like an endorsement but isn't meant as one. In the end Millholland was the last vendor standing. They came in ~ 10 % less than Baker's best & final offer with Baker being a bit less than Sullivan. At the time of contract signing, according to the CSI database, I wound up paying the lowest price per STC W of any Sunpower residential PV system in the state of CA as of 08/2013 which was my contract date. I also believe I got more than I contracted for in ways that added some class to the work.

As for current prices, at least in my HOA where we're beyond 150 installs or a bit better than 25 % penetration and all the roofs are either flat and mostly liteweight concrete or mission tile concrete, the average current installation price is ~ $2.50 - $3.25 or so per STC W, depending on size, complexity of the job and also, to a degree larger than most folks either know or want to admit, the customer's lack of knowledge of what they're getting into and also negotiating skills (more and better than the bluster or methods that tough guys who think they're good negotiators use because they think rancor and attempts at intimidation make for successful negotiating more than product knowledge and empathy.

In the end, everything is negotiable. Just keep the goal of a good system at a fair but vigorously negotiated price over low buck. Low buck as a sloe criteria is the errand and goal of a fool.

Lastly, get your roof inspected and serviced. PV will last a long time. Make sure the roof under it has a high probability of lasting as long. Chasing leaks under an array is a big PITA you don't need. Your payback will be when the rains start up next winter and you sleep warm and dry.

Welcome to the neighborhood and the forum of few(er) illusions.