It all depends on the tint, haha!!
There are various levels of quality, heat rejection, etc. I was looking for maximum heat rejection, which usually means going with ceramic film. The dyed films are much cheaper, but only offer limited heat rejection with anything other than super-dark “limo tint” (like 5%). You could do limo on the back windows, but you’d be taking a chance with it on the fronts, and there’s no way you could run that on the windshield.
Besides, I like a “medium” tint all around, (I went with 45%), and after the positive experience with windshield film on my Smart EV, I knew I wanted it on that huge Bolt windshield too, haha!! So 45% all around, 70% on the windshield. Also, there are 7 windows on the Bolt, plus the windshield (total of 8).
Within ceramics, there are more levels of quality. 3M Crystalline is probably the top film in this category.
Spectra PhotoSync goes beyond that. The level of tint changes depending on solar intensity. Darker when there’s more sun, lighter at night, etc. Even the “clear” (70 or 75%), which is installed on the windshield, has amazing heat rejection. On the Bolt, the windshield is slanted and huge (might be the source of the trouble with the Light Ash interior and glare??).
With an EV, it’s all about energy efficiency. So, the less heat you have pouring into the interior, the better your range if you’re running the climate control.
(BTW, I’m not a hypermiler…I believe in using an EV just like an ICEV. I use the A/C when it’s hot, the heater when it’s cold, the defroster when there’s frost, etc.)
After the tint, the next variable on cost is labor. Extreme Autowerks isn’t the least expensive shop by a long shot, but I’ve never seen a better install job than what Bing and his crew do.
As an example, there are no seams on any of the widows, even the windshield. That takes skill and experience. They only use deionzed water. There were no bubbles, specks, or voids. And as I said above, you literally couldn’t tell they’d been in the car, save for the tint on the windows. That’s huge for me.
You see all sorts of super high end cars in their shop, but they treat every car with the same care. That’s something I’m williiig to pay for.
BTW, I’m not affiliated with Spectra or Extreme Autowerks (other than being a totally satisfied customer)
All of the above: IMHO, YMMV, etc