From this page of the Disco Elysium guide, you will learn how to open the Trash container and what you can find in it.
There is a locked trash container behind the Whirling-In-Rags Hotel building – the place where you will come across the body of the hanged man. You have to open it to complete the Open trash container quest. This can be done in two ways.
Get the key
Getting the key is the easiest way to open the locked container at the back of the Whirling-In-Rags building. Enter the hotel and ask Lawrence Garte for the key – you will get it without any problems.
Use your strength
The second way is a bit more complicated, as you have to use a prybar and also pass the legendary Physical Instrument skill check. Your character can fail it if he doesn't have enough points in strength.
Inside the container, you will find the old clothes of the hanged man and two additional items:
- Denim jeans: starts the Who put the clothes in the trash? quest;
- Olive-drab military overgarment;
- Damaged Ledger: completes the Find your paperwork secret quest;
- Yellow-Man Mug: after finding this item, you will later be able to get more from Gary when interrogating him about the clothes thrown in the trash.