For €400/mo all in, split between my friend and I, I've got an air-conditioned office at the local business park with the back room stuffed with ~10 servers, redundant internet links with BGP announcements of our /24 so failover is transparent, and all of that is 10 minutes walk from home. Granted, the setup is more than a bit YOLO; the servers are in two piles rather than a proper rack and the fiber to the servers is just flapping in the breeze from the AC, but we've been able to fix literally everything that went wrong except for a power outage ~a year ago when somebody got a bit overzealous with a backhoe within 30 minutes.
The main difference between what we've got and a proper setup is on the order of about €5k of fixed costs, all of which have a lifespan of ~decades. The savings from owning your own hardware might shock you.
Also, if you think that the "professional" hosts do any better, consider that that Hetzner box you linked is a desktop machine shoved onto a rack shelf.
