

If you can get something your local university is discarding due to W10 end. Got my first server this way ( core 2 E-something ) when W7 EOL was anonced and it ran nextcloud very well. If you can’t, go for an used pc. The only thing you should buy new are disks.
Even if the hardware is not performant enough to run it can be a 2nd node for promxox.
Master make no sense. It fail to comunicate what role the default branch serve. Main is clearer, your default branch is the main one.