From the Super Mario Wiki
Retrieved from "https://www.mariowiki.com/index.php?title=Accessories&oldid=2848962"
The Accessories is a location in Luigi's Mansion 3. It is found on the second level of the Hotel Shops. It is left of the Gift Shop and above the Barber Shop. The yellow gem can be found here. Due to there being bars in the door, only Gooigi can explore this area.
When Kruller enters the Security Office, he drops a diamond key. Gooigi needs to get the key, then walk into the Accessories and open the cash register to get the key for the Boutique, and so on. When he gets the key, Goobs appear. He must defeat them, then proceed to the boutique.
The yellow gem is behind a glass case. Gooigi must use the Suction Shot on one of the suitcases in the center of the room and throw it at the case to break the glass, allowing him to get the gem and anything else in the case.
The cash register is in the northwest corner. There is an assortment of hats in the northeast corner, with coins under the top hat. There are glass cases in the southeast and southwest corners. The one in the southwest corner has handbags and coins, while the southeast case has watches and a Pearl.
If Luigi slams the stand in the middle three times with the suitcases, it will start to spin and then start to throw coins everywhere.