Adventure Labyrinth Story Restocking Fred with same stock
Each time you return from the Labyrinth, Fred will sell different stock. If he is selling an item you want multiple of without randomness, buy it. Then, go in the old well at the north east of town, exit it, and Fred will have a full stock of the same items he was selling. This is useful for Books of Attack/Defense, Phoenix Amulet, and Moof Tickets.
The image featured at the top of this post is ©The Legend of Heroes: Trails of Cold Steel III key art / Original