637 S. Main Street was a 19th-century buggy factory building built in 1989, once the home of the Ann Arbor Buggy Company, and reused many times over the years. Some of the property's history is discussed in detail in this Ann Arbor News Article.
- The 19th-century brick building was taken down in early 2017. The exterior facades facing Main and Mosley are expected to be reconstructed and incorporated into a new six-story retail/apartment development on the block. A neighboring car wash and the South Main Market were demolished starting in December 2016 to make way for the nearly block-long development.
- Firefly Club (-2009)
- The Neutral Zone (-)
- The Ark (second floor, 1984-1996)
- Raupp Campfitters, listed in 1975
- Berry's Red Barn, 1971
- Wenk's Downtown Honda (1967)
- Electric Wholesale Supply Co. (1957 photo in Ann Arbor News)
- Ann Arbor Co-operative Society (1939-1955)
- Ann Arbor Buggy Co. (at 635, in 1917 Polk Directory)
- Old West Side, Ann Arbor, Michigan: a report on the environmental survey of a neighborhood. By Richard G. Wilson, Old West Side Association, inc, Edward J. Vaughn, National Trust for Historic Preservation in the United States. 1971