Checklist for installing a PV system, and more - Solar Panel Talk

After hitting a number of speed bumps on my solar plans, I realized I wish I had a checklist of things I needed to do before hand.
So I made one, sharing it here.

Feedback welcome.
In order of importance from critical to needed to desirable
This checks if going PV Solar is even possible within 6 months
1. Is the roof OK for solar? (condition, orientation, protrusions, material, shade, etc.)
2. Breaker box able to handle the new demand? Take picture. Maybe call electrician.
3. Finances and/or credit score good? (despite the ad's, it’s NOT free!)
4. Home Insurance OK with solar? What limits and changes to coverage?
5. Utilities policy on solar (net metering, credits, or nothing at all)
5a. (Home Owners Association policy, usually no problem, but on rare occasion...)

This is very important for financial planning and system design
6. Collect at least a years’ worth of electric (If plan to replace appliance, gas too), get digital copy
7. Gov incentives, tax breaks and credits, discounts available?
8. Talk to your tax person if they know about above (may be good to hire in this case)

These are optional but should be considered:
9. Home battery
10. EV charge port

If possible, take pictures of roof in full sun as close to December 21st and June 21st, every hour from 9am to 3pm (or more if you want). Calculated shadows are great, but the best is photos at the lowest and highest sun angles. Solar sun calculators do factor trees, but not chimneys and antennas on neighbor’s house.

ALSO:
Will you do home electrical upgrades or replacements? Gas to electric?
Is so, may look at a new breaker box, of even go with a smart system.
Is your house service enough, or will you need to manage needs, or upgrade service? All that's sound observation but there are other things to consider before any of that.
I'd suggest keeping the horse before the cart.

Before you do anything else:
- Get educated about solar energy and know what's really available and what best fits your application. This is especially pertinent for attempts at DIY. Most folks don't know the first thing about PV, walk in clueless and get screwed by their own ignorance. I've seen it more than 100 times up close and personal. Seems like everyone I've spoken to who has PV in my HOA who's read as much as a magazine article or talked to an equally ignorant neighbor considers themselves an expert.
- Set goals you want to achieve on paper before you start. It's always good to know where you want to go before you draw a roadmap of how to get there.
- If saving money is one of those goals, maximize conservation considerations/lifestyle adjustments and estimate their effect on annual load before beginning system design. You'll save $$ twice, once for the lower bills the conservation efforts enable and second for the smaller system that a lower load will enable. Know too that a 100% bill offset may not be the most cost-effective way to go.
- Be very careful about vendor selection and start that process at the beginning of preliminary system design which, with your self education you can do most of yourself. Beyond some basic level of quality, equipment is a now largely a commodity. That makes equipment selection easier and raises the importance of a high-quality vendor. A quality vendor has always made all the difference between a good job and a job that's nothing but trouble.
- Don't get trapped in the low buck, first cost syndrome. It's false economy. Negotiate tough but fair and never, ever reveal prices to vendors. That is, don't fall for the price match game - it's a trap that will lock in a price.

Take what you want of the above. Scrap the rest. most important thing is keeping your purchase price low or rather your $/watt low. Should be aiming for $2/watt, not much more than that. There is way too much customization and trying to "right size" solar systems, and this leads to huge inefficiencies which is why the installers charge such premiums in the US. The whole 'how much is your energy bill' line is a car salesmen type trick to get you to overpay. So is the low monthly fee that is a loan for 30 years. Insist on $/watt price and a minimum size instead. I have found very few installers who want to separate the equipment cost from their labor. That is because they are jamming in extra profits on the resale of the panels and other equipment. I find panels for less than $.60/watt all the time (retail, not wholesale), but most installers charge about $1 or more. I've been looking at redesigning some of the solar mounts and manufacturing them in a lower cost manufacturing environment. The cost of aluminum is very low, so $80-100/panel for mounting equipment is outrageous and that is not far from the norm. Finally, optimize for your roof not for for the power from each panel. The cost of panels is so much lower now, trying to get the most power from each panel is actually suboptimal. Eg. you only lose 16% using a 10° tilt vs a 30° tilt (at 37degree parallel). But you gain up to 50% more panels because of less inter-row spacing. You lose less than 2% by optimizing the azimuth to conform to your roof shape (up to 20° off of dead south, or 180°) and you can fit many more panels on your roof.