Integration of an LMS into an existing wordpress website

We are operating a website ([login to view URL]) running on wordpress, where we offer free content, as well as subscriptions to our clients. We now want to add a LMS System to the website, where we can sell courses. Requirements for the LMS:  Various categories for different topics  For each category we can add different classes (Websites that contain Video, Audio and Course description)  The clients can buy single classes out of a category, or buy bundles of classes  Membership page where the client can see his purchases  Include payment gateway with automated invoice creation (clients receives an invoice, and a copy is stored at the backend of the website)  Application of discount codes is possible What we need from you:  Identify a plugin that meets the requirements  This plugin needs to work with the current website theme  Make the setup and implementation of the LMS in our website, including payment gateway (credit card and paypal) and invoice creation What we provide:  Purchase of the plugin you suggest  Webdesign of the course pages  Support in the process (teamwork) Please consider: So far our website works very well and we already serves plenty of clients. For the management of the monthly subscriptions we use „Paid Member Subscriptions Pro“, and we intended to continue using it for our monthly subscriptions as we have good experience.