Hi,
I have experience in mailing server set up and configure mailing application and pass all records.
I will do all:
n-house server
CentOS 7
nginx latest
php-fpm latest
MriaDB latest
postfix
dovecot
DNS
multiple domains with DKIM/SPF
configure 24 e-mail addresses for 14 domains
Please refer to the document attached
SFTP, SSH, Webmin, Virtualmin, Google Suite
Thank you