CMS System

I am creating an ecommerce website and would like to create CMS to back it up. I would like my content management system to do the following: 1) create the capability of upload documents that need to be processed in that users profile page. 2) take the customer to a shopping cart exit page 3) once they have checked out and paid. Deliver all their uploaded documents to be processed to an output page that is used internally. ## Deliverables 1) All deliverables will be considered "work made for hire" under U.S. Copyright law. Employer will receive exclusive and complete copyrights to all work purchased. (No 3rd party components unless all copyright ramifications are explained AND AGREED TO by the employer on the site per the worker's Worker Legal Agreement). 1) create the capability of upload documents that need to be processed in that users profile page. 2) provide customer with capability of adding another service or checking out. 3) take the customer to a shopping cart exit page 4) once they have checked out and paid. Deliver all their uploaded documents to be processed to an output page that is used internally. 5) the output page should sort the orders by product. ## Platform not sure, open to suggestions maybe one of the open source cms systems.