A custom calendar for users in my wordpress website

This is the way my website currently works: A client posts a project, artists bid on the project, then when the client chooses them as the winner they click "choose winner" button and they are redirected to paypal to pay a fee. After they pay they are redirected to a custom page. So instead of being redirected to a custom page I want them to get redirected to the artists calendar to set appointment. . Maybe you can do this custom work for me?. I need a calendar script for my wordpress website for artists on my website. I need artist to be able to set their open schedules and get notifications when they have new appointments. Also the admin needs to have access to everyones schedules. Also remember my website has thousands of artists so i need to make something easy that they all can have their own personal calendar. I have looked at many plugins but none of them come close to one that I could use, here is one that almost was similar to what i need, maybe you can make new one or you can customize this. [login to view URL] I want my calendar to look like this: [login to view URL]