Sandra comes from a poor background. Her husband died while working as a constructor and she raised Rebeka on her own. She used to run a haberdashery, but she was quickly forced to close it due to a shopping mall which opened in their neighborhood. Then she searched for a new business, and entered the drug dealing world.
She quickly became rich and, at the beginning of Season 2, she had enough money to buy Guzmán's and Marina's old house and move in. She justifies her wealth by saying that she won the lottery.