Very nice bin setup. I just use free pallets for my compost bins, but I do have the front system where I drop down boards along a rail as I fill up the bin. I just fill up one bin and then move on to the next bin - no turning in my pallet compost bin system. It takes a long time for a pallet bin to compost without turning, but I am willing to just let it sit and compost on its own for a few years. Almost all my compost comes from my chicken run compost system where the chickens do all the work for me.
Yes, a very nice bin setup, but I, too, immediately thought of the current cost of lumber and how expensive it would be to build a nice compost bin setup like that. Hence, I just use free pallets that I scrounge up from wherever I can get them.
I mentioned that in addition to the free pallets, I also use boards in a rail system to drop down the front of the bin as the material builds up. I like that system as it reduces the amount of lifting I have to do until the bin reaches towards the top and completely full. Last year, when a 2X6 was like $200 a board, I went through my scrap pile(s) behind the garage and started to piece together some scraps to make them 4 feet long for the front rail system. I just connected the pieces together using pocket hole screws on the end to end butt joint. Not a very strong board, but good enough for the purpose on the front side of the compost bins.

At the current price of a 2X6X8 pine board at Menards for $12.00, I was able to pocket hole screw a couple scrap pieces of wood with only about 20 cents of screws. That saved me about $6.00 per board for the front of the compost bin. Some of old wood I dug out from the scrap pile was definitely not very good, but I figure I'd use it for the compost bin and if the old wood failed, I will just remove the pocket hole screws and reuse them on some other scrap wood to make more 4 foot long boards for the front of the compost bins.
As for the wooden raised beds, last year I had to pass on all wooden raised beds like I usually make. I changed over to making raised beds out of
corrugated galvanized steel and using only 2X4's to make a frame panel to screw on the sheet metal. I used 4X4 posts cut down for the corners of the raised bed and used my pocket hole screws to attach the panels to the 4X4's. The galvanized sheet panel raised beds worked great for me last year, so I bought some more sheet metal to make a few more of those raised beds this spring.
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Again, I used scrap lumber to make the panel frames, but since I did not have enough scrap lumber at 8 feet long, I had to make 2 raised beds 4X4 each. But, having a couple smaller 4X4 beds instead of one 4X8 raised beds has some advantages. Also, since I was able to make my builds using only scrap lumber, I only had to pay for the galvanized metal and my pocket hole screw.
A full corrugated steel panel measures 26 inches wide by 8 feet long. I cut the panel in half at 4 foot, and then in half at 13 inches high. So, my finished 4X4 bed is about 16 inches high when attached to the wood frames. It cost me less than $25 per raised bed using my scrap wood. If I had to buy the wood for the framing, it still would have cost considerably less than an all wood raised bed.
If anyone is interested in the corrugated panel raised beds, here is a YouTube video which is close to what I built.
Bringing the post around to the topic of compost, I used the hügelkultur wood concept to fill the bottom 8-10 inches of the raised bed and then mixed my chicken run compost with top soil for the top 6-8 inches. Those corrugated panel raised beds worked out great for me last year and I have 2 more ready to build this spring.