Wordpress Theme Customization for Freelancer Site

I need to further customize a Freelancer-type Wordpress theme that has already been modified.

Current Features:
- Employers can post projects and view received proposals.
- Employers can award projects to multiple freelancers but currently cannot hire more than one.

Required Modifications:

Employer:
1- being able to Award and Hire any, many or all Freelancers for a project.
2- once project is awarded to Freelancer/s, Create Milestone option must be available for all awardees.
3- being able to cancel or revoke the project from hired freelancer/s.
4- being able to send a review about the Freelancer on how he managed or completed the project.
5- if awarded the project to Freelancer/s, Freelancer/s must receive notifications about it.
6- must be able to see all payments and milestone details on dashboard Statements.
7- being able to Delete or Hide proposals he received for a project.
8- being able to send messages to Freelancer/s who sent proposals.

Freelancer:
9- Freelancer/s being able to send private messages to Project owner.

All related links and notifications must open its correct page.

You must assume all the above tasks are new and must be created and added to the theme by yourself.

All modifications must be made to child theme and these modifications must be intact even with theme updating.

You will be given ftp and site admin only, NO cPanel access will be given.

You maybe working on a c.lone as there are lots of custom works so, if any issue, I can prove from my original site.

No placeholder bids are accepted. Your bid price is FINAL.

Only experienced WordPress developers can bid for this project.