People tend to use either the plastic rectangle organizer caddy or a mesh bag type with outside pockets. The first one seems to be meant to stay in the shower. I wouldn’t want to haul in up and down the hall and it doesn’t stand on its own.
You will take your carrier and hang it on a hook or sit it on the floor near the shower or the sink while you are in the communal bath. The toiletries bag (#3) is popular with guys, especially as a short travel bag or for the gym, for a razor, shave cream, hair stuff, deodorant, dental needs. They might be too small for a full size bottles of shampoo or body wash, so keep that in mind.