BTW, Mitsubishi makes ductless systems that would mount the condenser on the roof (you said you are on the top floor) and the evaporator in the room with only a couple small holes through the roof for copper refrigerant lines.
BTW, Mitsubishi makes ductless systems that would mount the condenser on the roof (you said you are on the top floor) and the evaporator in the room with only a couple small holes through the roof for copper refrigerant lines.Bingo, best solution. I was going to post it but read the threads first.
Mitsubishi is on the higher end of the price scale but there are a number of brands to look at.
Swamp coolers, as we call them out west, will not work in your climate.