The two men at the center of a fatal shooting outside the Empire State Building on Friday had brushed shoulders for years — often literally, two large egos stuffed into a small office — and yet could hardly have been less alike.

Neighbors and co-workers described them: Jeffrey T. Johnson, 58, a slight, meticulous artist, the first one to work in the morning and the last one out, without so much as a look outside for fresh air in between; Steven Ercolino, 41, a well-built, confident salesman used to getting what he wanted when he wanted it. The artist chafed at what he saw as the salesman’s casual bossiness, they said, and the two never got along.

Years passed this way at the company, Hazan Imports, which sold handbags and belts, until Mr. Johnson was laid off almost two years ago.

And yet, the casual observer would not have known it, to look at him. He put on the same suit every morning: the Upper East Side’s own Willy Loman, dressing for a job he no longer had. He picked up his newspaper on the front stoop and walked two blocks to McDonald’s for breakfast. Months after his dismissal, he showed up at the building where he once worked, across West 33rd Street from the famous skyscraper, and confronted the salesman, a much larger man, in an elevator. The two came close enough to blows — Mr. Johnson throwing an elbow, Mr. Ercolino grabbing his throat and threatening him — that it was reported to the police.