Maybe just save up $200 and buy a portable AC unit instead of a ten
I own one. The portable ones have a rather limited efficiency. Ours brought the air temperature down to 23-24°C in the sleeping areas during the daytime.
After switching it off for the night (the things are incredibly noisy...), temperatures quickly rose to 26-27°C again (at least at reduced humidity due to the AC).
And that was in a ground floor apartment...
And opening windows doesn't really help any more if the minimum outside temp still is >20°C during the night and the air is basically motionless.