I'm not sure if this is still valid advice. I'd just stick 64GB of memory in a desktop PC and have the home lab running on VMs. 5 years ago I left a company ru

I'm not sure if this is still valid advice. I'd just stick 64GB of memory in a desktop PC and have the home lab running on VMs. 5 years ago I left a company running loads of enterprise software and web applications for other companies in a couple of data centers. We had well over 10.000 physical machines. When I left, about 90% of the workloads were virtualized. Running on bare metal is the exception today. Sure, its cool to have hot-swap HDDs, hot-swap PSUs, redundant network cards and a remote management board but none of that is rocket science. You can learn it in a week if needed. Networking is a much deeper topic yet almost nobody would recommend you to set up a couple of switches and hardware firewalls in your home network. Today you expect that the hardware just works. In the real world it is extremely complicated to correctly design and run networks, but you aren't going to experience any of these problems in a home lab.