Living in a very overpriced 1200'sq home in southern California, where the high temp finally got below 90 this last weekend (the average for the last 30 days, day and night combined, was over 80 every day), and the house has no insulation and none can be added without lots of holes in the ceiling to blow in minimal insulation, I totally feel ya! Without a window AC unit in the house turned on at noon and kept running until 8-9pm, my dog would probably be dead by now. It's usually 10 degrees warmer inside than outside due to all the sun baking the vaulted ceilings.
I had several days where the bedroom was still too hot to sleep, so I pulled a
mattress into the living room and slept there so the AC could keep my midwestern-raised blood from boiling off in my sleep. I wish I had found the house before the cheapo house flipper did, so I could have filled the walls and ceilings with blown in insulation before the drywall was put up. I would have also planted a couple fast growing fruit
trees along the south wall to shade that surface a bit, and grow some food. Instead I have a nearly worthless shed there, but my 7 fruit trees in other spots are growing in their heavily mulched spaces now. I'm tempted to remove the shed and espalier something there, but with less than 5 years to retire and move I'm not going overboard.
Sadly a lot of options are removed with the packed in, cookie cutter neighborhoods where house orientation is based on maximizing housing units per block. There was a nice development where California state law will require new construction to include
solar panels, which is a nice step forward.