The quote is fair for what they offer, but to me, steam is not where to start. Cost on a evaporative pad based humidifier, installed, should be under $1000 even if labor is $100 an hour.
Also note that steam is generated with an electric heater, which can get expensive, quickly, fast, all heating season.
I think I would start with a evaporative pad system, and then add steam, if you still have a humidity problem. Who knows with coming from the desert, you might not need the humidity of someone from the tropics, to feel comfortable.
HVAC guys say my whole house humidifier works well, wife and I are too dry, but we also are not 20 anymore either.
39F outside with 41% RH and 76F inside with 33% RH. With an Aprilaire 560 working whenever the condensing natural gas furnace is running, in Baltimore, MD.
Two different HVAC guys I have had into the house, said humidifier was working well, one of them told me before I even asked.
Neither one wanted to sell me a new whole house humidifier, unless I wanted to buy steam humidifier. House is 1600' split level. We run 2 tabletop humidifiers full time, one hot (sucks electric), and one cool.
Other information, mostly house efficiency stuff, if not interested, it is not worth reading.
I had an Aprilaire installed at the same time as my condensing furnace, a few years ago. I had an energy inspection done, at a '75% discount' from the power company. It seemed legit, and not a profit deal. I got a blower door test, a couple of IR pictures, 12 CFL lamps, and a 3-4 page report for $100.
The end result, was if I use one of about 150 'approved' contractors who service my area (almost everyone)- The gas/electric company will pay me 50% of my cost to install insulation up to $2000 out of their pocket. So my home leaks bad, it seems, and that means that humidity is going out with it.
This seems like it is not a scam for money, just a way to hit state mandated avoided costs. I just can not get enough humidity in my air. I guess I will start with the half price insulation. BGE for gas/electric if anyone is interested.