You can spend a lot of money building a homelab that competes with small office networks. Or, you can do what I did and build a network of cast-off, unwanted hardware.
A thrift-store Synology NAS, “parts-only” Thinkpad laptop with a cracked screen and broken keyboard, and a $5 goodwill router, flashed with OpenWRT forms the basis of my home network. Proxmox, a free hypervisor allowed me to test LXC and docker containers, block ads on my network with Pi-Hole, run a test Windows Active Directory environment, run Windows95 as a client VM, and host my BBS on this collection of cast-offs.
I’m happy with it, and am always looking for new ways to upgrade on the cheap.
I’ve wondered if I could add another hard drive to the system, or speed up the storage. I found this post after a web search – apparently, Thinkpads support SATA Express, an older technology meant to bridge support between SATA and NVMe drives. The drive interface is backwards compatible with SATA, but provides 2 PCI-x lanes (instead of 4 with native NVMe).
While a compromise, it appear to be quite a bit faster in testing.
And, I’ve found adapters that support 2 NVMe drives on one SATA port. Add 2 drives, set up a ZFS pool, on a laptop – the mind boggles.