Place Ghostbusters signs at Holly Hedges, Dirty Docks, or Pleasant ParkAgain, we are dealing with a relatively simple challenge, especially since everything is indicated in the title. So go to Holly Hedges, Dirty Docks or Pleasant Park to place Ghostbusters signs.
As for Holly Hedges, for example, we find three: at the level of the large house in the northeast, west side in front of the large greenhouse and on the south, in front of the large house. If you want to go to Pleasant Park instead, there is a sign in front of the yellow house to the west, one in front of a cellar entrance to the east, and a final one to the north.
To place a sign, as always, you just have to interact with place with the indicated key.