My general rule is never pay a deposit up front.  I think most guys feel the same way.  

Also, $125 an hour sounds impossibly too good to be true. Therefore, this whole set up screams scam to me.

I'm surprised the responses all focus on a $40 deposit. A lot more damage can be done with a video-blackmail, outing, etc-and Illnois's 2 party consent law isn't going to really protect you from the lasting damage this could cause. It's very easy to record a screen (without your knowledge) without ever initiating record within the app itself. I'd say no to anyone who wants uncontrolled access to my face and a private conversation.