Build a Website like imgur.com -- 2

We want website like [login to view URL] and it needs to have different sections for images and videos. Users should have a point system e.g.; for signing up they get 1000 points, for uploading image 100 points, for videos 200 points, leaving comments 20 points and so on. Admin panel should have modules to control front end, users, content and pointing system. All content will have options to be shared to other social media sites. Content will have options to be watermarked. Login/signup/signin using social media sites and direct login/signup facilities too. Must be SEO optimised using user provided content Must be mobile friendly Payment in milestones - 25% advanced, 25% on completion of site - 50% before all testing done by client BUT before site goes live and uploaded to clients hosting.