Also, add 2FA

Biggest hurdle would be timing, if you want it sound right… Every speaker should be in sync as much as possible

Basically every serious mailserver package has imapsync included. I don’t know what kind of hardware you’re running and what you expect from the server doing the copying but running webmail, search indexes, antivirus, etc will cost you ram. There are solutions aimed at keeping backups of your mail though, I can’t give you recommendations, the only thing I remember is that they don’t give you a normal webmail or imap, instead you get a web-interface aimed at searching through the backup(s)

I don’t know for sure but I think it’s the current, higher voltage will bridge a bigger gap/higher resistance but a human body doesn’t have that high of a resistance and car batteries are capable of providing plenty of current (I think?)

That’s a different problem (that doesn’t really exist where I live)

This is why I trust motorcyclists more than cars. A manual doesn’t change this problem, a motorcycle does.