50 USD for WebRTC deployment on a Wordpress website

Hi, I need a WebRTC application/integration to able users on my WordPress website call each other by video calling. The website in question is this one: [login to view URL] It is an Online Therapy, about telepsychology. an Online Psychologist website where patient meets a psychologist. The WebRTC must be integrated in a way to turn possible only logged users communicate each other. Also, we need enable to call only patients who made an appointment on the platform. Please take a look at my website. I accept any suggestion from you about which WebRTC streaming platform to use. - Please provide your quote and estimation time. - My base budget available is about $40~$50. - Get in mind I am quoting with other developers so I will hire the cheaper one. - My deadline is February 28th, 2018. If you need access the WP Dashboard or the cPanel to evaluate my environment, please asks to me and I will provide temporary access to you.