Building off of the work done by last year's capstone team focused on this question, our team is looking to fill this gap between legal advocacy and data-based work on housing quality. Based on a model of predatory landlord behavior, we identify indicators in public and private data sources that point to the systematic and illegal harassment of tenants (focused on but not limited to rent stabilized tenants) by New York City's landlords. This comprehensive set of methods can help bring rigor and extensive coverage to the data-driven investigations of landlords suspected of engaging in predatory behavior. The case studies we present in this paper demonstrate this, while also showing the unique nature of each landlord's portfolio and set of suspected predatory tactics. Ultimately, while it is not possible to use data to prove definitively that landlords are engaging in illegal behavior aimed at harassing tenants, the set of methods presented in this paper, when applied together, can paint a damning picture of a landlord by showing they are likely engaged in a plethora of predatory actions throughout the property ownership cycle. While not a finding of statistical certainty, the repeated flagging of a landlord of suspicion for a variety of predatory actions suggests that each flag is not an outlier but rather one piece in a larger picture of predatory landlord behavior.