I have a total cool - NOT the cheapest option by a long stretch, but it was really bought for my campervan so it is the only one that runs off the leisure battery without flattening it (because my dog comes everywhere with me). It is brilliant, but for a shed you can go cheaper. It is very effective, but it is what it is - it can only cool when there is air flow (so you need a window open) and it works by putting moisture into the air, so it won't cool in high humidity. In sunny Scotland it has worked really well, and made a huge difference - but it doesn't really cool the whole room very effectively, it cools what is in front of it. In the van I have it aimed into the crate, at home I have it aimed at the bed (not needed it for the rabbits so only canine and human testing!). So you need to consider where you will point it to make best use of it.