I have kept a personal server for decades in one form or another. At the moment running two Optiplex 9020s (Intel I7, 8GB RAM) one running TrueNAS (and several USB hard drives) and the other is the "app" server running Debian LTS. I prefer local servers because I can usually get far more bang for my buck at the cost of the headache of putting it on the Internet. The power cost to run both is the same as a cheap VPS. Recycling old consumer/SOHO tech is probably the best bang for your buck.

File sharing, BitTorrent, and version control are my mainstay applications I've run on my servers over the years. File servers are out of trauma; I've lost too much data to trust software or hardware, and servers are the easiest way to configure stuff like RAID/ZFS as well as automated backups. BitTorrent on a server lets me be a good citizen and seed consistently. Version control right now is Forgejo, and given the nonsense at Github this is becoming a better decision by the day. There are also a number of support services like PostgreSQL and NGINX, with CRON powered backups to the fileserver.