How did Juliette Gordon Low get the money to start Girl Scouts?

Savannah, Georgia. In fact a biography of her is entitled Lady From Savannah.

In order to start the first American Girl Guide troop, Juliette Gordon Low called her friend, Nina Anderson Pape, who was the principal of a girl's school. Miss Pape suggested a group of girls who went to Mr. Hoxie's camp in the woods each Saturday. The daughter of Juliette's cousin was a member of the group and was able to interest all the girls in joining the first American Girl Guide troop.

Juliette also registered her niece, Margaret "Daisy Doots" Eleanor Gordon as the very first member, although Margaret did not attend the first meeting.

Source: "The Girl Scout Story" by Adéle deLeeuw 1965