Which chain of events correctly accounts for the conditions described in the excerpt?

These men earn their living by cruising the streets long before daylight, collecting old automobile parts, pasteboard, paper, rags, rubber, magazines, brass, iron, steel, old clothes or anything they can find that is salable as junk. They wheel their little pushcarts around exploring cellars, garbage cans and refuse heaps. When they have a load, they turn their footsteps in the direction of the American Junk Dealers, Inc., whose site of wholesale and retail operations is located directly opposite the pushcart colony at 134th Street and Park Avenue. Of the fifty odd colonists, many are ex-carpenters, painters, brick-masons, auto-mechanics, upholsterers, plumbers and even an artist or two.

Which chain of events correctly accounts for the conditions described in the excerpt?