Gantolandan's Home is the house where Gantolandan resides and is located in the district of Southeast Baldur's Gate. The house is a corner house in the cluster of houses that occupy the center of the district. The Blade and Stars is across the street and a generic home is on its left. The front door is unlocked.
The ground floor is unpopulated. The chest is locked with a DC of 50 and contains 29 
. The bookshelves contain copies of the History of the Fateful Coin and History of the Ulgarth.
On the second floor, Gantolandan can be found sleeping on the middle bed. The chest of drawers is trapped and locked with a DC of 30 for both and contains a Rogue Stone. The bookshelves contain copies of the History of the North VI and History of Waterdeep I.
Quest[]
The house is visited during the side quest Narlen's Heist.
Also, Narlen will still want to rob the house (the second heist of the quest and regardless if you've already killed Gantolandan) to prove your worth as a thief. So you still must meet him and Rededge outside the Blade and Stars to start the robbery. However, you don't need to go back inside the house, just go back to the Thieves' Guild Stronghold and talk to Narlen and be sure to have the rogue stone in your inventory.