How did Olga's grandmother buy her own house?

When Olga's grandparents had come to the U.S. from Puerto Rico, they lived in a tenement. Abuelita had saved her money to buy a house, but her husband left. So she found an upstairs rental apartment. She saved money and the landlord gradually warmed to her and her family. When the neighborhood became too Puerto Rican for him, he offered to sell the house to her. She bought it.