Customer Management System

We are a Hosting Company and we have huge amount of resellers that host with us and use as there hosting company for there clients. We also host for general public and not only Resellers. We need a system which basically maintains all the resellers and general customers and all billing and sales. And also gives our resellers to manage their clients and set their own pricing structure so they should also be able to send invoice to there clients. This system should be able to send marketing newsletter as well. Resellers should be able to place orders from this systems and we should receive orders in email and as well in the system automatically. There should be a Help Desk Support Ticketing System also included in this system. We have purchased Member Management System and Help Desk System from "www.expinion.net" and we need all these systems combined into one complete system with the added above functionality. We want the exact same quality of work as www.expinion.net. You can test their demos to see if you are capable of doing it. We will provide you the complete source for those applications as it is which you must modify to meet our requirements.