It's a 1 person part-time job. Most of the work goes into coordinating package updates with Ansible. I can include $1000 in the calculation if that makes you feel better ;)

Everything is deployed with Ansible, monitored with Monit. The servers have redundant PSUs and SATA hot-swappable HDDs, so you can fix minor hardware issues without having to reboot. As the result, we have more than a year of uptime on a typical server.

On the other side, we've been hit with several S3 outages. My feeling is that the cloud needs fully automatic fail-over because it is failing much more often than all our bare metal server combined.