3:30:11gotwfBlackbeard: Tell your ISP that you want to _purchase_ a static IP "add-on" package. Once you shell out that you can reasonably demand that they create a PTR for your domain.
3:36:41gotwfsome will sell you a single IP, others as a minimum block, e.g. 5 usable. Whatever, just get the minimum package avail, and then the PTR.
3:37:17gotwfBlackbeard: you also need to confirm that they are not doing anything lame like blocking port 25
3:38:24Blackbeardgotwf: OK 🤔 so they might be blocking SMTP
3:38:36gotwfBlackbeard: And if you want remote access to that smtp server, then you will use port 587 as "submission" port for authenticated/authorized parties.
3:39:02gotwfsome block port 25 in the name of spam deterrent
3:41:38gotwfthere a lot to setting up smtp and imap servers correctly and securely but once you get teh config, you don't need to do much else other than patch as appropriate.