Looking at getting one for my greenhouse. If you have one, how does it perform for you? 

We borrowed one to go camping. It worked well except when we woke up in the morning the tent got very hot. 

The venting out of the room's heat is a problem for most units. It is sort of counter productive to have the exhaust's heat coming back into the space where you want cool. It is the nemesis of a portable a/c. Found one rated 4 stars at Lowe's. Tomorrow will be a nice hot day to try it out! 

I just want to know what the best portable air systemnfor my courtyard so my chihuahua can keep cool. 

I just want to know what the best portable air systemnfor my courtyard so my chihuahua can keep cool. 

I just want to know what the best portable air systemnfor my courtyard so my chihuahua can keep cool.

Forget the portable air systemfor. Buy your Chihuahua a leather Fonzie jacket and it will be cool forever. 

Heeeeeeeeeeeeeyyyyyyyyyyyyy