...some work there on occasion, so yes, cooler would be better, 3) our new freezer feels like it is overheating trying to stay cool, 4) our contractor said AZ code doesn't allow branching in a duct from one of the home's AC units due to new carbon monoxide code.

I'd like to do a mini-split we can run at nights or when in use, but don't want the cost. A swamp cooler seems cheapest, but I've read you need to leave a door open or a vent available. I'm going to take what was mentioned here and ask an AC guy.