I've looked into having rooftop solar installed a number of times, and every time I've walked away with the feeling that I don't know enough to know what to watch out for, and that there was a high probability that any company I dealt with would be trying to take advantage of my ignorance.
A typical grid-tied home solar system has 3 big areas of component costs:
1. The actual solar panels.
2. The thing that mounts the solar panels in place (called racking)
3. The things that turn the solar panel's electricity into electricity that can be used in your home and by the grid. Typically inverters and wiring.
The good news is that you can price this all out yourself, to get an idea of what your system SHOULD actually cost. Then you could theoretically do it yourself, or be a more informed consumer when shopping around to have someone do it for you.
I haven't pulled the trigger yet, but I've been planning, revising and tracking prices on a DIY install for the past couple years.
Here are some of the resources I like:
1: Unbound Solar is a good resource for ready-to-install DIY kits. Their kits are a good resource for "this just works" - and you can then price out individual components as-needed. - https://unboundsolar.com/shop/solar-kits?product-category=gr...
2: For buying actual panels, I like A1 solar. They seem to have the best selection/pricing I've found: https://a1solarstore.com/
3: OpenSolar is a free tool designed for solar installers, but available to DIY'ers. It lets you specify your panels, racking, inverters etc., and then lay them out no your roof or the ground. https://www.opensolar.com/ - It's very likely the tool that the contractors you're getting bids from are using.
The last bit of info I'll share is that in general, microinverters don't make sense from a cost/benefit standpoint. Panels have gotten really cheap, microinverters haven't. You're probably better off adding more panels with a traditional inverter system vs. paying for microinverters to get marginal efficiency gains from a smaller number of panels.
There seems to be some DIY advertised costs that might be better. Really, this is mounting stuff on a roof and wiring it to your garage. While there is code and best practices, this is not disassembly of your car's transmission.
I'm hoping DIY practices and experience disseminates over the next decade, as well as cheap-good perovskite+silicon panels and sodium ion/sulfur/solid state battery storage.
I am not affiliated with the below, but saw DIY kits - your comment reminded me others might have experience. One quote that is interesting "With the current tax incentives to go solar, our DIY solar customer’s average ROI is less than 5 years."
I also think there is a place for solar company that ignores the hard sale and leases. Even better if they focus on efficiency and getting the installation price down. Franchised or training companies would also work.
As prices drop, it becomes possible to pay immediately. Or get a small loan. I wish they would ban solar leases.
It's not obvious to me that rooftop solar panels will still pay for themselves (in the past there were subsidized rates that made the math work better) but being able to run off batteries+solar "microgrid" in a power outage for a few hours is a quality-of-life improvement that I'd consider for the right price. (There's some of this in corporate offices, luxury apartments, etc.)
The jackery is roughly 30% more expensive but feels a lot less fragile than my homemade stuff, and I've moved all my device charging (tablet/phone/power tool battery) charging over to these systems.
It was a fun project! Cabling is always the part that sneaks up on you so make sure to plan out the cabling / what plug types you want / crimp or buy / etc. ahead of time.
Also Panels, inverters and batteries are all quite different and have varied pros and cons and installers are typically getting kick backs from specific suppliers so their advice is not impartial
The only thing the installers have to figure out is how to wire up the panels with your inverter in the right ratio, and if your roof can hold the panels you want. The rest you pick and they do.
Don't get an offgrid inverter, hybrid grid-tied inverter all the way. Even if you live in the sticks with no grid, just get a hybrid one.
Also, don't worry if your batteries will last the night or cloudy days or whatever. Just make sure you have enough to handle your load if it goes down, the rest works on its own and the inverter just blends your solar with whatever it needs from the grid.
Would you please expand on why a hybrid inverter is better even if you're not going to grid-tie it?
But also hybrid does everything you need and the cost savings of something else is marginal from what I've seen. It's an "all in one" that I believe is a good one size fits all for 99% of the houses out there. Every house should have a 5/10kw inverter installed by default with a corresponding set of solar and battery pack. I.e.
5kw solar panels, 5kw inverter, 5kwh battery bank. Or 10 or 15. It acts as a giant ups, let's you shift some power, and you can gradually reduce your grid reliance to almoat 0 by adding more batteries, all while staying on the grid just in case.
My quick take is that there is enough competition to ensure reasonable prices for solar equipment (panels, racking, electronics, etc.). However, a lot of manual labor goes into a rooftop installation that's comparable to other trades like plumbing, electric, roofing, construction, etc., which means that if your local cost of living is high, then the labor cost will be high as well. Until we have robot labor, I accept that other people need to put food on their tables as well, so I don't think that a lot of overhead in a solar project's cost beyond the materials is necessarily evidence of exploitation.
This means that you can online-shop and build a cheap system (I'm sure under $2 per watt is easy). But it needs to be shipped to you, lifted onto the roof, mounted, and finally wired to your grid. All that is pure labor. I did everything except the high-voltage wiring and the conduit runs, and I bet a competent version of me could have done everything I did in three 10-hour days (it actually took me twice that). Where I live, California Bay Area, you can't get any tradesperson out of bed for less than $100/hour, so that's at least $3,000 in labor. The electrician, permitting, and re-patching the roof around the new mounts added another $4,500 -- again, mostly labor and/or bureaucracy.
That makes about $7,500 to install maybe $10,000 of equipment. I avoided about $3,000 in labor costs by spending at least 60 hours of my own amateur time, including mistakes, worrying, second-guessing myself, and other activities that a professional wouldn't have done.
I learned a lot. I understand the difference between microinverters and regular ones; I know more about split-phase residential electricity in the US; I appreciate how a system design trades off cost and efficiency for issues like "clipping" when an inverter can't handle the full output of a PV panel; and I know way more than I ever wanted to know about the foam, insulation, tar, gravel, and wood that make up my roof.
In retrospect, I'm glad I did the project because of the knowledge gained, and because I now have even more respect for the skills and effort that are needed to put solar on a home's roof. But would I do it again? Probably not; I'd rather have paid the extra few grand to have someone do it for me while I stayed cocooned in my office, writing code.
TL;DR: profit is being made in residential solar, but I believe most of it goes to honest labor.
Here in the Netherlands, the norm is that it's a single day of work by a crew of two. That includes everything you described: rails, installation, repatching, wiring, inverter, basically the entire package.
If my estimate was 30 hours, and your estimate is 2 x 10 hours (assuming 10-hour days), then we're mostly in agreement.