It says "This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center. Closed 10 years ago."
However, I found useful-to-me information on running commands as root before starting a service running as a less-privileed user.
The OP wanted to create directories for subversion, and finds out about systemd tmpfiles.
But I found out about "ExecStartPre=+" which solved by usecase of firewall adjustment as root before launcing a service.