Build an OPENCART extension that will help me to manage my freight / forwarding company.

Hello, I want to extend OPENCART so that it can help me to manage my warehousing and freight forwarding company. My goal is to automate as much as possible ... - The receiving of client's cargo arriving at my warehouse. Upload of photos, and descriptions of cargo. - Setting and billing of "required" and "optional" fees for received cargo. - Allowing client to see and interact with their stored cargo, in their account. - Giving client the ability to consolidate/combine their cargo, and estimate shipping expenses from my warehouse to any destination. - Requiring client to enter descriptions and values for their cargo. - Easy checkout process that shows client which cargo is being shipped, and what the related expenses are. - Acceptance of all major credit cards, most likely through [login to view URL] - Direct messaging system that allows administrator and client to contact each other and reference specific cargo and shipments. - Automatic messages to clients as the status of their cargo/shipments changes. - The uploading/storing of all documents that are created during the international shipping process. I want to use OPENCART as a foundation because it includes a client area, security, a checkout system, and is extendable. This new functionality will require extending the front-end and the back-end of OPENCART. *** Your modifications must be built as an extension. I want to retain the ability to update OPENCART after your work is complete. Here are examples of companies that currently operate warehousing and freight forwarding companies successfully: - [login to view URL] < -- A simplified version of this website would be perfect for my needs. - [login to view URL] I am ready to begin immediately. Let's talk.