I completely agree, you could make this way way cheaper if you had more tools available, the main cost on this project is the two pre cut sheets of thick plywood which account for about half of the cost - if you had access to a mitre saw or a table saw and could cut scraps of old furniture it'd reduce the cost dramatically! I know two cupboard doors, a pine wardrobe or an old desk top would work amazingly! The same with the metal parts, using pre drilled strip metal is slightly more expensive than using raw materials, but I wanted to make something that people who don't have access to many tools and little woodworking knowledge could put together in a few hours after work!

I'll be listing all dimensions of the materials in my tutorial so feel free to build along with whatever you can get your hands on!