Why cost ranges vary so much
A shallow repair in open yard is very different from a deep line under a driveway, sidewalk, retaining wall, tree, or street. Access and restoration can drive as much pain as the pipe work itself.
Trenchless methods may reduce surface damage, but they still require the existing line to meet technical conditions.
What a useful quote includes
A useful sewer quote names the method, footage, depth, access points, permit handling, cleanup, restoration, warranty, and what happens if conditions change once work starts.
Ask for the reason behind the recommendation, not just the price.
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.