Balbus was a Roman citizen and slave owner. While he could not afford to buy a slave, he found Vanessa after she accidentally went back in time and accused her of being a runaway slave. Since she could not refute this claim, he took her as his own. He quickly realised she was very knowledgeable, and spread rumors that she could tell the future.
When Gnaeus came to his home demanding to ask her his son's location, he required that they pay to see her. Eventually, Gnaeus wanted to buy her, and Balbus showed his greed by not wanting to give up "his little gold mine" and spent a long time haggling over a price. (PROSE: The Stone Rose)