Video streaming site -- 2

We are launching a video platform. It will have a subscriber function and a payment portal. Two type of users on two domains, the content producer and the content buyer which will reach the site using two different websites that will look the same but have different text. I want you to make use of existing technology and not build everything as that will take far too much time. I want you to propose a streaming setup that we can modify rather than creating it from start. I do not want to build this on WordPress! I am not interested in discussing wordpress I don't want wordpress at all! My budget is very very limited for the first stage of this project and once we have validated the website with paying clients we will run a larger project with increased budget.