Damaged Room Hidden Package
Make your way to the rundown yellow mansion on the northeast corner of the island. Head inside and you'll see a room on the first floor to the right with a broken wall. Head up the staircase and stand on the broken walkway across from the opening in the wall. Then, carefully jump into the hole to fall into the room with the Hidden Package. It may take a few tries as the jump is a bit janky, but you'll get it.
Why not jump back to our Vice City Interactive Map or check out our full Collectibles guide for more help.