DIY Bucket Swamp Cooler $120-$200 - depends on if you have any of the materials. $200 if you have nothing!
No Air Conditioner? No Sweat! Build A DIY Swamp Cooler - Northwest Public Broadcasting
DIY Air Conditioner From a 5 Gallon Bucket for Under $25
DIY 5 Gallon Bucket Swamp Cooler
Do Swamp Coolers Actually Work?
Make a DIY Bucket Air Conditioner
Homemade Evaporative Air Cooler! - Simple Box Fan Conversion - EASY Instructions!
How to Build your own DIY Air Conditioner
I made a DIY swamp cooler as a low-cost way to stay cool at night. : r/redneckengineering
Steps to build a FigJam bucket cooler. : r/BurningMan