During the course of your project, some additional work may be needed, either due to a requirement of the client or, it might be something initially overlooked or something required by the team, with no extra cost to the client. In these cases, you can mark a User Story as a client requirement or as a team requirement.
To mark a User Story as a client requirement or as a team requirement, go to its details page and then, on the Sidebar, click 
for team requirement or 
for client requirement; click the same buttons again to remove the marks.
