I had my water line replaced because it burst and flooded my property overnight. When the water was turned back on, they discovered a slow leak coming from under the house (slab, some inaccessible crawl space under the addition).

They told me they'd have to re-pipe the entire house. Does that seem right? They quoted 4k (small, one bathroom house). Not sure how to proceed from here... can't they just replace whatever pipes may be the issue?