Shelly Levene is one of the older salesmen in Mitch and Murray's satellite office. He's been selling investment properties since the 1960s, and he was once very good at it. Now in the early 1980s, he can barely close a deal. He blames his streak of "bad luck" on the poor quality of leads he's given, not on his sales technique—which hasn't changed since his early days in the business. Levene is desperate to do well in the monthly sales contest so he can keep his job to give money to his daughter, who is either ill or in similarly dire circumstances. This desperation leads him to rob the office and sell the premium leads to Mitch and Murray's competition. Levene represents the common man who works hard but has nothing to show for it.
Richard Roma is the top-earning salesman in Mitch and Murray's four-person satellite office. As such he gets the best leads, which allows him to stay at the top of the office leaderboard. Roma doesn't limit himself to the sure bets, however. He's always selling, even when he's ostensibly taking a dinner break. That's how he meets James Lingk, whom he interests in a plot of land after just a few minutes of conversation. Roma's sales pitch is both self-assured and casual, and he presents himself as a friend and confidant to his prospective clients. Underneath his cordial and supportive demeanor, Roma is always looking out for one person: himself.
Humorless and stoic, John Williamson runs Mitch and Murray's satellite sales office with a combination of fear and spite. He makes sure the men under his watch know their jobs are at risk if they don't perform, and as he controls the distribution of the leads, he gets to decide who does well and who doesn't. Williamson seems outwardly unaffected by the salesmen's taunts about his position, purpose, and social life, but he always gets his revenge in the end. He unwittingly sabotages Roma's deal with James Lingk, knowingly gives Levene leads that will go nowhere, and turns in Levene to the cops after saying he wouldn't. He represents the corporate greed and control that prevents the common man from getting ahead.
James Lingk, initially dining alone at the Chinese restaurant, is drawn to Richard Roma by the salesman's open, friendly manner. During the course of their dinner conversation, Lingk and Roma begin to discuss Glengarry Highlands. Chastised by his wife for what she believes is a foolish investment, he tracks Roma down at the office, demanding to cancel the contract and retrieve his check. Devastated when told the check has been cashed, he storms out.
Struggling to make sales, Dave Moss is furious about the sales contest. As an act of revenge against the company's management, he plots the robbery and convinces Levene to carry it out.
George Aaronow seems the least dishonest of the salesmen. He refuses to commit the burglary even when Moss tries to blackmail him into doing so. Even though he doesn't participate in the robbery, he worries that Moss may lay blame on him.