Well, the desired temp inside is 70F, the bars behind the foiled window was 80F, and the ones behind the filmed window were 95F. So I would say yes.
I've found that the tinting doesn't do much good. We have burglar bars on the inside of the window so as an experiment, I put my laser thermometer on the bars of a window that had tint vs one that had foil (both on the same wall) and it was a 15F difference. We're in TX, so it's been over 100 every day for the past two months or more.
The wife hates the wasps, so might have to skip this one :p
Single pane windows, would shutters be a frugal fix?
To be frank, I'm not sure if replacing the single pane with double pane is: A - something I can afford at the moment and B - something I can DIY (which adds to point A).
I have a feeling that the windows are a large part of my electricity usage (due to AC constantly running), I have them "foiled" and really tempted just to board them up. Before I go to that extreme, I was thinking maybe there's something I can attach to the outside that would essentially add that 2nd pane, or at least block some sun from hitting the glass.
suggestions?

Is there a solar powered light (for the yard) that attracts bugs, but is not a bug zapper?
Wanting to relocate some wild frogs/toads, they seem to like a certain flower bed because the "night light" on the house brings the bugs. My thought is if I make another area enticing, they will go there.
Is this a load bearing 2x4?
I need to enter the attic via this gable vent hole, unfortunately I can't fit. My thought is maybe I should install a 2x4 against the (what I assume is original) lighter colored beam to the right, and another for good measure at the left side of the hole.
thoughts?