See 311 housing complaints against landlords of the apartments you're looking to rent.
HomeReveal uses StreetEasy.com's interface to empower tenants with the transparency they need to find a new apartment. While users search for new apartments in New York City, they can see the number of, and details on 311 housing complaints from the last 5 years against the property they are looking at. If an apartment has any complaints, it will appear in a highlighted shade of yellow under the listing. Users can view the details of those of complaints by clicking the "see more" button, either while scrolling through many listings at once, or while on a specific listing's page.
To see what it's like, start at this link: https://streeteasy.com/for-rent/brooklyn
If you want to turn HomeReveal off during your search, simply go to its icon at the top and toggle it off.
All data is taken from the NYC Open Data initiative's 311 archive.