For my clients I want to set up a support system in my

Hello,

For my clients I want to set up a support system in my website which is powered by wordpress. Whenever client needs to communicate with me he can simply visit my website, login using credentials and do the needful, like:

- Raise a support question
- View invoices online
- View contracts online (Just stored files in pdf)
- Communicate with me using website as communication tool and not email
also, one client should not see what other people are posting, like on a forum. It should be client specific system.

While for admin, i.e. me, I should be able to see all request in one single dashboard. Assign priorities, reply, mark them close etc. System shall generate invoices every month and send automated email to client and send follow up emails if status is unpaid.

I want to understand how this can be achieved? This shall be available only upon login and not to general users accessing content of my website.