I thought so. But how much would "a lot" be? Can a single person do it by himself?
Of course, there is no reason why a single person couldn't do it. Heck, I have been running my own services for years now.
In practice, you'll need to know how to use Linux and its CLI. Practically all server-software is run and configured from CLI, with no GUI-tools, so you need to know what you're doing. You'll also need to fully understand how to set up port-forwarding and firewalls correctly in your router. You need a domain-name and some DNS-server directing requests for that domain-name to your IP-address -- I have bought severals domains from Namecheap and I use their DNS, but there are plenty of other options out there, some of which are free.
Once all that's in check, install e.g. Nextcloud for cloud-storage of files, to keep contacts, calendar and files in sync between multiple devices, including phones, tablets, desktops, laptops etc. OpenHAB or Home-Assistant for home-automation. Haproxy or similar for reverse-proxy. Look into how to use containers, like e.g. Docker, Podman or LXD -- I, personally, far prefer LXD-containers. And so on.