The number of hours the videographer will stay largely depends on whether they charge by the hour or by wedding event. It is ideal that they stay for the duration of your wedding celebration or at least the biggest moments, so if you are paying by the hour, go over your wedding programme and make sure that the hours you are considering hiring them for will cover those moments. If the videographer charges by event, it's still a good idea to go over the timeline of your day to receive their confirmation.