Need a functional site similar to udemy.com or skillshare.

Need a functional site similar to [login to view URL] or skillshare. Please mention the price of the total script (I'm not set on the range I give, but I must be made aware of what I am paying for). We require one who already done such a project. Please provide the demo link and evidence of doing this project before (I know its fairly common). It's compulsory. So if you don't have demo links please don't reply. Requirements: -PHP, scalable, integrated with paypal and some way to accept credit cards. -Teachers can create and sell their own courses online (documents, blog and videos), or offer tutoring services in person/events (offline). Site takes a certain commission. -Three types of teachers: tutors, professors, institutions, each can describe who they are and their qualifications -Students register on site for free. -Login/Create profile with Facebook or academia.edu. Share courses and services with major social media outlets. -Logo is already developed, but site must have a clean and simple look like betterfly and udemy with big bold text. This has to be high quality and not buggy. Describe how you work to me as well (IE guarantee of quality and how the project will proceed). Want a satisfaction guarantee. Thanks.