Sewer problems here split predictably between root intrusion in the older streets and settlement in the newer subdivisions.
Old Village and mature streets
Clay and early cast iron laterals leak slightly at the joints, and the large live oaks along these streets send roots straight to them. Once inside they mat and catch everything. Cutting is a seasonal fix; lining removes the joints and stops the cycle.
Newer subdivisions
The pipe is sound PVC, but ground settlement over fill can leave a low spot that holds water and collects solids. That is a section repair rather than a full replacement — and only camera footage distinguishes the two.
Long laterals on large lots
Bigger lots mean longer runs from house to main, with more opportunity for a belly or a root intrusion somewhere along the way. It also means locating the fault precisely matters more, because digging in the wrong place is expensive.
Never quote blind
Roots, a belly, a crack and a collapse are four different repairs at four very different prices. If someone has quoted you without showing footage, ask to see it.