Find all the RC cars and see Adam's memory in Helena's mind.
This is missable you must collect the first 3 before entering Helena's mind.
The first RC car is near room 017, the second RC car is in the dining room on the second floor, the third RC car is behind the dumpsters near the tattoo shop, and the fourth is in Helena's mind when you will walk through her mind with a TV in your hands, there will be a moment when the door to your left will shut, and you'll have to go forward and then turn right it will be on the table.
Enjoy the 40g