According to Denver assessor records, 1221 Clarkson Street was built in 1962. No building permit could be located to confirm this date, but the dingbat building type, popular in the 1960s through the early 1970s in Denver, suggests that the building was constructed around this time. Isabella Lana purchased this property in 1961 from Maude Williams, who had owned it since 1928. It is likely that Lana was responsible for the construction of the apartment building. City directories show that Isabella Lana was the wife of Justin Lana, president of Lana Plastic Manufacturing. During the 1960s and 1970s the building was known as the Mark LeRoy Apartments (sometimes listed as the LeRoy Mark Apartments). Lana retained ownership until 1979.
