What you will need:
-6 vinyl shutters
-4- 2x4's 8 ft long, each cut into 3, 30 inch pieces ( I know what your thinking, why didn't I use 3-
2x4x10, yes I know a 2x4x10 cut in 4 equal pieces is 4- 30 inch boards. But 4 8fts are cheaper than 3 10 ft boards)
-Box of deck screws (3inch long)
Screw 4 30 inch pieces together to make a square.
Now screw 2 shutters to each side so they are standing on end, side by side.
Make sure the slots are pointing up so the compost does not fall out when the bin is filled.
And there you have it.
I made 2 of them and put them side by side. I guess I could have built one that was 2 bins connected but I didn't think I was going to need 2 until I got the first one filled.
Total cost: -2x4's 10.28
-box of screws $2.99