Create a Wordpress Plugin -- 2

I want a wordpress plugin - email client with following functions: > It should be similar to gmail in looks and functioning. But all functions of gmail are not required. Also need to add some functions which gmail does not have. It will be like blend of gmail and wordpress. > The plugin would have two aspects Admin dashboard with setting options, and front end login for users and admin. from where he/she can access mail, compose and work on email like gmail. > Read, compose, attach files, check all email folders and other email functions which have in gmail but can do it through wordpress plugin List of some functions: > front end user /admin / group manager login > Login page with company branding (Company Logo) > Sidebar / header / footer company advertisement / branding > Admin can see list of user accounts in a sidebar and check any mail > Group creation for different dept. like sales, HR, etc. > Folder creation option i.e. important mails / resumes, etc. > Mail search option on top > Email auto forwarding to user (access by admin permission) > Email threading ( reply from same email mail) > Star imp. emails. > Mark as read / unread > Add signature in email > Auto response > Remove BCC / CC (should be Optional) > Who is logged in status > Create group of users like sales, HR, billing group for emails. Group manager can see his group's all mails in list and check mail of his department's users. See the picture attached. > User can not see all list of users. He can see only his user name when login. > Admin can see list of all users and check all group and users mail. > Admin can give right to auto forward email and other settings to users or group managers, but by default users can only read and compose their own emails. > Customize login branding and other branding in sidebar as in picture shown. > group manager can write / compose mail to entire group or individual. Similarly admin can... > other mailing functionalist and settings Once the plugin created I need support for a year. Also If I need to add or remove some functions in it the plugin freelancer must be get it done. I have attached some snaps about how it would look like. We may need to add many things in it, it is for reference only.