The cabins next to Bayside Cemetery were established by Florence Mastine (husband Charles) and were called the Sunset Cabins. Florence acquired the land from a Scott Wentworth in 1925 - 1930. The 1940 City Directory lists them as the Sunset Cabins with proprietor as Florence Mastine. I believe the Mastines had two sons, who assisted in operating the cabins in later years. The family owned the cabins until 1965, when the property was sold to your great-uncle. You can access the deeds and read details at the Belknap County Registry of Deeds' on-line site.
http://www.nhdeeds.com/belknap/BeHome.html