So on average once or twice per 5 years per server. Remote hands are also service you can pay for.

Most expense is initial setup and automation, but once you get thru that hump and have non-spiky loads it can be massively cheaper

You can also pay smart hands to do that. My experience with Equinix for example it's been great.

My experience with Equinix varies wildly by facility and somewhat by which tech gets the ticket. Chicago has been good, Seattle tolerable, Dublin is dumber than rocks. We flew somebody up there rather than take chances for a big project.