He apprenticed with the carriage blacksmith firm of Scott and Watson in Guelph, Ontario, then moved to Vermont and Massachusetts, where he and worked producing Concord Wagons and Wells-Fargo stagecoaches.

He soon struck out on his own, working in multiple places in the 1860s before finally making his way to the City of Flint in 1869.

By the 1880s, Paterson's firm employed ten people, and could build one buggy and one cart per day.

He constructed the first part of this building on the corner of Third and Harrison Streets; upon completion, he was the largest manufacturer of vehicles in the area.

Other tenants included Baker Business College, a Social Security office, the Internal Revenue Service, and a variety of commercial and industrial firms.

[2] The William A. Paterson Factory Complex consisted of four major buildings occupying approximately one-third of a city block.

The oldest building was a single-story brick-and-wood shed, probably built in the late 1870s or early 1880s.