If you would like to keep rooms cooler, the best option is a portable AC unit with an exhaust hose. A hole can be cut into the interior wall for the exhaust hose to run out and then down through the mansard to exhaust through the soffit. It will need to be trimmed on the outside in brown, of course, with some sort of covering to prevent rodents or pests from climbing in through the hose. One of our residents, Wayne Ely, has done this for other units. His phone number is 863-660-6748 in case you’d like to ask him about it. Of course, anyone you choose can do it, as long as they don’t cause damage to the building.