A few times a year Lowes and Homedepot have this kind of timber on sale at $1.97, normal price is $3.97. I just found they are on sale at Lowes now at selected stores. But this is not advertised and YMMV. My local store is $2.17, still good price.
Landscape Timber [lowes.com]
I have bought a many in the past year, built a few low retaining walls and raised beds, even some outdoor shelves and table legs. It's not the top quality but does the job. For about $2 I don't expect too much.
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