Below is a walkthrough for the Inspection Assistance Wanted support quest in The Legend of Heroes: Trails from Zero.
Client: Inspection Officer Quattro
Salary: 2000 mira
Head to Station Street and enter the Crossbell Station. Once inside, head up the stairs and speak with Inspector Officer Quattro on the left in front of a door.
Accept his request follow him through Platform 2, which is at the bottom of the stairs on the south side. Next, speak with Inspection Officer Quattro near the entrance to the train.
When you gain control, speak with all the people inside the train car. Once you’ve spoken with everyone, a brief cutscene will trigger. Afterwards, speak with the family of 3 then speak with the guy sitting alone on the back right side of the train (behind the lady wearing a white dress).
After the cutscene ends, the quest will complete! Make sure to report it at the terminal.