Was wondering the same thing while I built mine over the last few weeks. I watched a ton of videos, but many are out of date on the software side. I mostly used the site that Quantumantics@fedia.io linked to, which seems to cover most everything. e.g. you no longer need to flash the BIOS if all you want is dynamic memory allocation, there's a userland utility now.
I printed my case, but there are some available for purchase on eBay and Etsy. Some 3D printing sites let you request models be printed to your specs.
Anyway, I'm happy with the build and the performance, but... This thing is loud, and given the limitations with power options (no sleep mode?) I'm still trying to figure out how to integrate it. If I could reliably power on and off remotely, I could stash it somewhere and use Steam Remote Play. But I've not had much luck yet.