My current plan is to buy/have my brother build myself a cheap computer to run as my server. Only will be using 2-3 wyze (or other) cameras. Doesnt need to be fancy, would prefer to have recording 24/7 but be willing to look at motion detection if that is easier.
This is a very good question, but not so easy to answer since it depends on so many parameters and what you want to do
The price of the camera is not important here, but the resolution is critical and many other parameters. If you stop with 2-3 cameras the new Intel i5 with 4 cores should be fine or even better the i7 if you want to have high resolution. 8 GB of RAM is fine. 4GB works also.
There are many posts about this in the forum so search. The latest one is this which can give you a good insight Super Bad FPS - But Xeoma works with the same setup
Another way is to buy a used server system running on Xeon processor with 4-8 cores. These systems are very cheap and you get a lot of computer for your money.
For the cameras, make sure you have the URL how to connect to them. Best is if they support the ONVIF standard which makes it so easy to connect them to Netcam Studio.