Yay for rescued bus dogs!!!
We full time in our bus with three cats, two dogs, and a goat. Unless it's over 95 degrees outside, they're perfectly fine in any spot because we painted the roof white, use reflectix in the windows, and have screens so we can put the windows down without anyone escaping. All our insulation is stock. We also have a window AC that we use when the humans are in the bus, but we never leave the bus unattended with the generator running. If it's too hot for them to be without AC, we just make sure we're in the campsite too so they have have the air.