Most jobs begin with clearing the line and a camera inspection from the cleanout. The Town's Master Plan says about 70 percent of Rockland homes were built before 1980, so many laterals have been in the ground for decades, and the video should show their joints, material, and any root entry.
Plumbing permits come from the Building Department at Town Hall, which doesn't do inspections on Fridays. If the repair reaches the Town connection, a Sewer Department permit and an approved drain layer may also be needed, so ask the plumber to list every approval in the estimate.
Because wetlands and floodplain districts run throughout town, Rockland zoning requires at least 22,000 square feet of upland per lot. If your lateral passes near a wetland or a flood area, ask whether the dig needs any extra review before it's scheduled.