Yeah, 100%. It's one of the reasons I did the job myself. I got 3 quotes ranging from $8K to $20k for what I wanted, with a wide range of details either missing or presumed that didn't sit well with me. Plus, this way if something goes wrong 250 miles from the nearest city, chances are I can fix it or bypass it. For example, I designed in large WAGO connector that will allow me to bypass the inverter in 2 minutes and run the whole Airstream from a generator or shore power if the inverter fails. None of the estimates I got had anything like that designed in.
For home solar on the roof, what they never tell you is that someone is going to have to come and remove everything if you ever have to have a new roof put on. And they're going to charge you about 2x what you spent to have it installed in the first place because they're taking it off and then putting it back on again with new hardware. The ONLY time I would do roof solar is if my roof was less than 5 years old, and it was a top quality roof to begin with, so it would last the life of the solar panels.
This ceases to be a problem if you have enough open land space to mount the panels closer to the ground, or so that they actually form the roof of a pole barn or something.