WATCH: Here are the developers with the most lien activity

Contractors and subcontractors often get into spats with clients and one another. Take One57, for example, where the building’s fire sprinklers are the cause of an ongoing dispute with the developer and project’s general contractor. Federated Fire Protection Systems claims that it’s owed $2.1 million for installing a sprinkler system from the building’s 21st floor to its roof.

In a situation like this, the first step to challenge a disputed bill is to file a mechanic’s lien — a claim against a client’s property that assures a contractor gets paid. In The Real Deal‘s April issue, we assembled a list of private developers and landlords with the most liens filed against their properties in Manhattan and Brooklyn — by dollar volume — over the past five years, based on data from PropertyShark. According to industry sources, a slowing market and tighter construction-financing tends to create an environment where liens spring up like mushrooms after the rain.

To see the 10 developers with the most lien activity since 2012, watch the video above.

For more videos, visit The Real Deal’s YouTube page.