Tale about home mail server

There was a poor web programmer and he decided to somehow install a server in his home. But not simple, but so that everything was like people: a web server and mail server. To the great happiness of this programmer, there was a new firmware with a ready mail server for the already existing home hardware QNAP 109 Pro II .
No sooner said than done: there is a permanent IP address from Avant-garde , the domain name * .spb.ru has been registered for a long time, the corresponding records on the FirstVDS DNS server are registered, the mail server is installed and configured. There was no limit to the joy of a programmer: mail goes straight home, sent from home instantly.

But that was the end of the joyful part of the tale.

A few days later it turned out that some free mail systems do not accept mail from a home mail server. Technical support from Rambler explained that the home server is represented as 192.168.XXX.XXX, and they do not deal with such bad servers. In the standard settings of the web interface of the XMail server, nothing suitable for the greeting value was available. Our programmer rummaged through the Internet and found how to change the value for the HALO command for the XMail server; it turns out that you need to add a new HeloDomain variable to the server configuration.
Now the mail server began to be presented as it should be, issuing the domain name from the * .spb.ru zone, but the mail was also rejected by the Rambler and Mail.ru systems. Polite technical support from the Rambler again explained to the hapless programmer that their mail server checks the PTR record of the server trying to send mail and if this value does not match the server's domain name, the mail is not accepted. In our case, the PTR record pointed to pppXXX-XXXXXXXXXXX.pppoe.avangarddsl.ru, which not only did not match the server's greeting value, but also assumed the use of a dynamic IP address.
Our programmer added the correct PTR record to the domain’s DNS records and waited. Days went by, but nothing changed, the PTR record still looked the same. After talking with VDS hosting technical support and experimenting with the ISPmanager Light control panel, it turned out that the PTR record on the hosting can be changed only for the IP addresses issued by this hosting.

What to do, maybe look for some other DNS hosting? Our poor programmer did just that. He registered and tested: free Xname and Everydns, and even paid for 1 year at webnames.ru . But all in vain - access to PTR records was not there. Finally, only in Relcom, where the programmer registered the domain name * .spb.ru, he was lucidly explained to him that the PTR record could be changed only by the IP owner, i.e. his internet provider.
In technical support avant-garde said that they do not provide the service to change the PTR. An email to dnsmaster @ from the SOA domain record pppXXXXXXXXXXXXXX.pppoe.avangarddsl.ru is back.
')
Dear habrasoobschestvu, maybe someone has experience placing a full-fledged mail server at home, share your experience? And what can you advise the hero of a fairy tale, so that the fairy tale has a happy ending? Maybe you can complain about non-compliance with clause 2.1 of RFC 1912 and should the Intenet provider make changes to the PTR record at the request of the client or not? Or it remains only to look for another provider? From technical support Web Plus and GenaralNet answered that they can change the PTR record, but it is still unknown what quality of Internet these providers have?

PS In principle, now I don’t really need a full-fledged home mail server, you can only receive mail, and send it via a mail server to VDS hosting. But after a while, in retirement, not paying for hosting - in my opinion a very tempting option.