Build a Website

This is not a website development project. I need to be advised about the best avalaible plugins to implement a management system as described below. Those having Authors role receive request trough a frontend contact form. Trough the plugin (or other solution) they must have the chance to manage requests received by using a communication system where message requests should have status like read, unread, waiting, rejected,archived (something like a simplified webmail management system). Considering it is just a study project consisting into finding and documentating the best plugin/solution in order to achieve the described feature the budget is 10USD.