One hundred and nine years ago this month, property lots in Harmon were experiencing rapid sales, according to a May 24, 1907 article in the Katonah Times. The newly developed community, located one mile north of Ossining on the Hudson River, had generated significant buyer interest despite being recently laid out.

The marketing campaign proved remarkably successful. A special excursion train from Grand Central Station on May 5 brought over five hundred prospective buyers, with nearly one-quarter purchasing property that day alone—140 lots were sold. Two weeks after the initial announcement, the promotional effort continued with strong sales on May 12 as well. Purchasers came from New Jersey, Brooklyn, and towns as far north as Albany.

Clifford B. Harmon of Wood, Harmon & Co., the developer, had originally planned to wait until June 1st to launch sales, but public demand accelerated the timeline. A distinctive feature of the development was a section reserved for bungalows surrounding a spring-fed lake—described as "a decided novelty in suburban development" that proved particularly popular with buyers.

The company's aggressive advertising emphasized the property's desirable location and easy payment terms, positioning Harmon as "the Highest, Healthiest, Most Beautiful, Most Accessible, and Most Aristocratic Part of Westchester County." The developer expected inventory would be depleted within a short timeframe given the enthusiastic market reception.