I think you can find it for sale on AliExpress by searching for ‘Topton N100 NAS motherboard.’

PiKVM or a similar device could work for OP - is that what you are thinking of? I’ve used it and it works well.

I think a lot of people who self-host get caught up in the excitement of getting the services up and running and neglect disaster planning, prevention, and recovery (myself included). Either they put it off for later or don’t realize it could be a problem down the road until it happens. We always say not to self host anything you can’t live without, and most take that advice, others don’t. Not saying OP falls in either category, necessarily, just adding on to some of your points.

Self hosting really is the land of compromise where we all have to balance our requirements, budget, time and effort. Personally, I have a little disposable income that I spend on hardware to host non-critical services so I can learn and tinker. It could all go away and all I will have lost is the time and money I put into it, but I gained some knowledge and enjoyment. Needless to say, I don’t have much in the way of backups and monitoring.

Not OP, but looks like the Geekworm KVM-A8. They also make a version using the CM4.