To transfer mail, most refined version IMHO, and one of the most affordable for your organization. Store common passwords - somewhere in the database, with access via a personal loan. Is, perhaps, not to share passwords at all, but usually require BONDS in a particular service that lived longer than any personal TIES (like, say, ME to the postmaster on the Internet, or admin access to the web hosting), then somewhere to store them.
Instant messengers as a means of transmitting passwords - technically an option, if fully controlled, or in the presence of end-to-end encryption. The rest will flow once, and well if will flow later expires.
PS: those who post passwords on public sites where a man or robot can read - SSZB.