This guy is a talker. That's really what he does. He spends his entire first scene of the play just talking to Lingk in what basically amounts to a five-minute monologue. At the end of the monologue, he pitches a sale to Lingk.
Like a football player doing a touchdown dance, Roma bursts into the office in Act 2. He's made the sale and won the contest, and he wants his first-prize Cadillac.
During the robbery investigation, Roma talks Aaronow down and tells him he has nothing to worry about.
Levine, doing a touchdown dance of his own, comes in and talks about the sale he just made. Roma celebrates with him and gets him to recount the sale.
Even the smoothest guys in the room get tested once in a while, and Roma's test comes in the form of Lingk, who shows up and wants to cancel the sale that he signed with Roma.
Come on, Roma's not going to give in that easy. He gets Levene to play a client of his, and together the two try to stall and confuse Lingk into giving up on cancelling the sale.
Williamson screws that whole thing up (like Williamson does) and Roma loses the sale. He flips out on Williamson, but can't keep flipping out because he has to talk to the cops.
Like a shark or some other ruthless animal that would be really cutthroat at selling, Roma tells Williamson that he's going to be taking half of Levene's commissions from here on out.