Does X have a say regarding cost, terms, and guarantees of service provided by the professional?
No, the terms and conditions of the provision are limited to users and professional, report in whichs; X does not gent involverd.
Does X help users decide what is the best professional for the service that they want?
Yes, canX dohelps the users help themselves, considering the quality and reliability of performance (in the special section of the Aapp), helping other users of X to move towards the best professional.