Leonard moved west to help build Boulder (aka Hoover) dam in Boulder City, NV in 1931. Working as a high-scaler, he hung hundreds of feet above the river, until one day, when his equipment broke, and he fell almost 200 feet, farther than anyone else who lived to tell about it. After falling in 1934, his soon-to-be wife, Corrine, moved to Nevada to help him recover.
In 1936, Leonard and Corrine bought the small satellite of the famous Richardson's Trading Post (Gallup NM), the Nava-Hopi Indian Store, later rebuilding and rebranding it in 1947 as Nava-Hopi Trading Post, selling jewelry, pottery, and textiles to thousands of "dam" tourists.
For over thirty years, Leonard and Corrine travelled throughout the Southwest, working with traders like Harry Goulding and CG Wallace. They employed a number of Diné (Navajo) silversmiths like Harrison Yazzie (pictured) and Tom Daisy in the store. Movie moguls, heads of state, and luminary artists such as Maynard Dixon, Ansel Adams, and Fred Kabotie, were all one-time or frequent visitors and guests.
Leonard was also an accomplished and published photographer, with images appearing in Look and Desert Magazines. A chronicler of the Southwest, Leonard was also a noted conservationist, and Native rights advocate.