First decision: cleaning or repair
A one-time clog may only need cleaning. Repeat backups, heavy root intrusion, offsets, pipe bellies, or collapsed sections can point toward repair or replacement.
Ask whether the contractor is solving the cause or just opening the line for now.
Use camera findings carefully
A camera inspection can show roots, standing water, breaks, offsets, and pipe material. It cannot always prove the full condition of a dirty or water-filled line, so cleaning may be needed before reliable inspection.
Get the video or screenshots if the quote is large.
When to treat this as urgent
If sewage is coming up through a floor drain, shower, tub, or basement toilet, stop using water in the house and get help quickly. Do not run laundry, dishwashers, showers, or extra toilet flushes until the blockage is understood.
If only one sink or toilet is slow, the issue may be inside the home. If several fixtures are slow or the lowest drain backs up first, the main sewer line is more likely involved.
What to ask before approving work
Ask whether the contractor has camera evidence, where the defect is located, whether cleaning alone is enough, and whether repair or full replacement is being recommended.
For expensive work, ask for a written scope that explains access points, restoration, permits, expected timeline, warranty, and whether trenchless repair is possible.