Leaving your car parked?

I work eight hours a day, five days a week in a cool air-conditioned office. My poor car has to sit outside in the hella-hot heat, waiting for the relief of being brought home to be parked away from the direct sunlight. I try to park my car under the one big tree we have outside of my office, but if I'm not the first one here in the morning I don't get the spot. Boo-hoo. So if and when I leave during lunch, I open my car door just to be attacked by the hotter-than-boiling-water heat that has been trapped inside and I have to stand there looking like an idiot, fanning my door trying to get that damn air out. That's with temps here reaching 96, at the most. I can't even imagine what the poor folks in California are going through with their temp reaching 116 or higher!
So there's this thing, Auto Cool Solar Powered Car Fan that helps bring the temps down in your car by up to thirty degrees. Thirty degrees might not sound like a lot, but it is when your indoor car temps are over a hundred degrees during the day. It's a little contraption that hooks right on to your car window and fans the hot air out. It's solar powered, so it doesn't require any batteries and you don't have to plug it into anything. I'm actually thinking I may have to get one because there is no way in hell I'm leaving my car windows open wide while I'm sitting inside my office, not being able to see my car. We're not in suburbia over here!