I have been looking at the data on the Raspberry Pi CM4 modules, and wanted to try the 8gb model with no EMMC and both Wifi and Bluetooth (The CM4108000), only to find that it does not appear to be available ANYWHERE on the web!
Whilst researching it however, I discovered this little Gem:
www.waveshare.com
It would seem that there has been a bit more development for the Pi than I realized. In fact, Waveshare has a whole line of carrier boards for the CM4 modules! Ah yes, competition, check it out!
Happy Trails,
Paul

Dual ETH Quad RS485 Base Board (B) For Raspberry Pi Compute Module 4, Gigabit Ethernet, 4CH Isolated RS485, USB2.0 | CM4-ETH-RS485-BASE-B
Dual ETH Quad RS485 Base Board (B) For Raspberry Pi Compute Module 4, Gigabit Ethernet, 4CH Isolated RS485, USB2.0 | CM4-ETH-RS485-BASE-B

It would seem that there has been a bit more development for the Pi than I realized. In fact, Waveshare has a whole line of carrier boards for the CM4 modules! Ah yes, competition, check it out!
Happy Trails,
Paul