Each team has an unlimited number of clients.
To join a new team, you should apply on their homepage by pressing the 'Request' button, choose who you want to be your coach, and fill out the application form (if the team has one). Once you apply, the coach you choose will review your application and decide whether or not to approve it.
No, only users on a Coach subscription can create and own teams.
Only you and your coach can see your diary, and no one else.
You can rate and leave reviews for teams and coaches you are currently a member of.