Boardsort.com is a good website to find answers from.
I think ewaste may have a website too.
Its actually pretty easy, there's set grades and mostly its motherboards, and the smaller boards and CPU.
Each one of those is divided into sub grades, like small and large sockets and laptop.
There should be backplane boards as their own grade though.
Biggest thing is, NO batterys. And NO excess metals, bolts, tinsel and CPU fixings.
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