Simple project Management system in PHP & MySQL

General information for the website: Project management system table and dashboard
Kind of development: New website from scratch
Description of requirements/features: We need a very rapid development of a project management system developed using wpdatatables or standard datatables js. System should:
- show a main task table comprising of all tasks in the system from all the projects
- table should be front-end editable with row filters/sort for each row
- Should be able to grant access to specific users to specific project IDs from the table
- when queried , project should show project start, end, and duration per task
- should have work packages->tasks-> sub tasks for task types
- able to query tasks by project ID or User ID
- able to get a pdf. of queried project/user

- Additional (if you can do it really quick, work breakdown chart and gannt chart for queried project, - will pay additional if you can do this)

* We have the tasks table in wpdatatables (wordpress) , we can provide the tasks table. work will be mostly to provide a dashboard for Project managers to view using the query conditions we require.
Extra notes: