You can put them in a case, you can put them in a rack, you can blast them into space. But you need to acquire them first. Historically I have purchased CanaKit Amazon Store starter kits.
Now that some of my efforts edge away from Proof of Concept toward Prototype, that starter kit approach becomes extravagant and limits evaluation of power supplies (PoE, battery backup, …) and other components of the grander system.
The triggering event is a desire to have my Zigbee and Z-Wave dongles available to Home Assistant (HA) over the network rather than be directly connected to the HA system which is almost certainly going to remain a container running in a VM running on physical hardware surrounded by a boatload of metal and electrical interference, not a great place for the radios, nor does mapping the USB devices directly into the VM and container happen easily.
Canakit rPi 4 8GB RAM full kit https://www.amazon.com/gp/product/B08B6F1FV5/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=B08B6F1FV5&linkCode=as2&tag=tgpent-20&linkId=cacc29c58e7fd340f4aa2b36e683002a