Limit responses in Contact Formulari 7

Good afternoon !!
I have created a form for the registration to some workshops.
What I need to get:
1-. That the same users can only register to the same workshop once.
2.- The user can register to all the workshops he wants, but would it be possible that if he enrolls in a workshop that coincides with the same time with another workshop that he has already registered, he will not be allowed to register?
3.- Is it possible to mark a maximum enrollment limit? When the workshop places are filled, the form will not let you sign up.

Thank you very much for your help.