Chinese Restaurant
The Chinese restaurant is a metaphor for the fact that these salesmen cannot go home. They can't go to their families or girlfriends, or empty homes to face the truth of their lives. Thus they linger in this transient place.
Lingk
The relationship between Roma and Lingk is a metaphor for the predatory nature of selling. Roma offers Lingk friendship and a shot at reclaiming his life because he sees the weakness in Lingk and knows he can exploit it and make a sale.
Broken Glass
The office is ransacked and there is glass shattered on the floor. Williamson's office being broken into is a metaphor for the desperate lengths the salesmen are willing to go to in order to keep their heads above water and make money. It is a metaphor for their desperation.
Train Compartments (Simile)
Roma speaks to Lingk about train compartments smelling like crap. He says that they keep them like that so that you get used to it. This is a simile he uses to describe the fact that Lingk's life is the same way, he's living next to human feces and he's become okay with it.
Desperation
The play in whole is a metaphor for the desperation of these men who work in a corrupt world of selling real estate. It shows that each man has a different need for which they are seeking to supply money to, in order to relieve the pain of that need.
