How to set up automatic replies to incoming e-mails?

Question

Mail server

We are a start-up company, we advertise on the Internet, and among the contacts we give our e-mail address (usual mail.ru).
We receive about 300 letters a day, and unfortunately we do not have time to respond to them. We decided that we needed some kind of auto-responder program, or, correctly, a program for processing incoming letters. We are only interested in three functions:
1. This program should respond to each incoming client letter with a pre-prepared template letter, the template has the ability to specify contacts and a link to the site. If the client wrote several times to our mail, then you do not need to respond to each letter, only once.
2. An automatic response should not come to the client immediately after he sends us a letter, but after about 2 hours (it is desirable that it be possible to set the time for a response letter)
3. Approximately after 6-8 hours (time can be changed) after the first response to the client, another template letter is sent from us to him (the template is already different).
These are all the features we need. You do not need to save, define incoming mail in folders.
Tell me - what program will help us with these functions. Or you need to order from programmers so that we write such a program.

Answer 1

Before the 2nd point, dig in Google, and after (point 2.3) you need to order from programmers so that they write such a program for you.
It shouldn't be expensive. Although this is relative.

Answer 2

https://www.lifewire.com/how-to-send-canned-replie...
although the topic has been on hype for five years, there are practically no non-SaaS programs

Answer 3

You can try to configure everything in xStarter. He knows a lot

Answer 4

This can be done through automation in the mailing service or through the CRM + ESP bundle. You can look into UniSender automation: https://www.unisender.com/ru/blog/novosti/privet-y...