setup email integration with website -- 2

I have a dedicated CentOS server that serves our cloud SaaS platform. What I need, is for each manager account the ability to add / set up email within their cloud SaaS dashboard so they can send/receive email using SMPT/Imap. This will allow the manager accounts to send/receive client emails and track history under each client profile account. I am particularly wanting to integrate for Office365, Gmail, and Yahoo email right now. This will need to be setup as we add new managers, the managers can add their own emails for client communications. Each of our clients are setup using an email address and a client_ID, if inbound/outbound emails match a client account, then it will be added to the client profile for historical records. We will need to be able to setup email templates so the system can be set up to send out automated messages based on criteria set from the manager. I will need to have an "ALERT" setup from within the managers dashboard so the managers can see when someone has sent an email inbound. If the system does NOT detect a matched email for a client, then we will not want to display the emails within the cloud SaaS dashboard. Based upon my last experience on Freelancer with an employee, we will not be placing escrow or releasing payments until the work is completed. I need this ASAP.