In the Tunnels 10 area (according to the map) in the lower left there are 2 junk piles and one barrel which are empty, but upon re-entering the area after some time they're always in ""unopened" stage. But still empty.
When freeing Buzzer (opened the cage) and talking with him before he gets to his desk, there is no barter window. Either make a barter window or remove the line until he gets to the desk.
