Taamar wrote:
So... do those window units actually work? How much volume will they actually cool? Do I need to install one for upstairs and a separate one for downstairs? Is this the sort of thing I can do myself? It looks like they are all for double-hung windows, I have side-sliding windows... is that OK? How much will they jack my utility bill (more or less than running 4 fans 24/7?)
Yes they work. They can be a bit noisy, as the compressor, etc. is all basically in the same room with you, but you get used to it.
For your type of windows you'll need a casement style window AC unit. If you google "casement window air conditioner" you should find some results that will work for you. They are self install devices. Basically you set them in the window (careful you don't drop it out the window!) then slide the window closed to hold it in place. Some have slide out wings that help to close off the rest of the window space, otherwise you need to cut some wood or plastic to fit the remaining open space on the window.
I'm not sure how much energy they draw, but if you only run it at certain times, etc. it probably won't be terrible. If you put it upstairs and then use some fans in various rooms to move the cool air around, you should be able to bring the overall house temp down and not just the room the AC unit is in.