If you have something laying around, you should start there until you know you’ll need more power/functionality. I got into homelabing/self hosting with two of these r720s I got for free. They’re awesome. I’m running multiple VMs, lxc containers, a NAS, and my power consumption is about 175 watts per r720. But my power bill is $0.11/kWh.

Update: for now, I’ll just set up a cron job with ClamAV to run on an LXC.