Below ground.
Better prepared.

A photograph or crack width alone cannot establish the cause or safety of a foundation. Movement over time, displacement, bowing, changing floors or doors, water and the building's load path matter together. An independent structural assessment is useful when those signs appear, the history is unclear or a costly repair is proposed. Sudden movement, falling material or a visibly unstable area calls for keeping clear and obtaining urgent professional help.

The answer depends on the work and the jurisdiction. Structural changes, excavation, changes in use and new building systems often involve approvals and inspections. Ask the local building department about the actual scope before signing. A contractor's license, product certificate or completed payment does not establish permit approval. Obtain the permit number, approved plans, inspection requirements and final status in writing.

Previous work is a reason to investigate the records, not an automatic reason to buy or walk away. Obtain the diagnosis, engineer's scope, permit and inspection records, installation documentation and warranty terms. Compare them with the current condition. A transferable warranty does not prove the cause was resolved or cover every future symptom. An independent specialist can identify remaining uncertainty before your purchase deadline.

Different quotes may diagnose different problems, stabilize different areas or include different restoration work. Put the proposed cause, repair objective, locations, quantities, engineering, permits, testing and exclusions side by side. A lower total is not necessarily a smaller price for the same work. If one bid proposes extensive piers and another proposes drainage alone, resolve the diagnosis before comparing financing or warranty language.

A repair may address one entry path while another remains, or collect water without removing its source. Record where water first appears, its timing relative to rain or plumbing use, and the operation of drains and pumps. Check roof runoff and exterior conditions safely. Groundwater, surface water, plumbing leaks, sewer backup and condensation require different investigations. Do not choose another coating or system only from the location of the final puddle.

An ordinary basement can be a better available refuge under public tornado guidance, but that does not make it an engineered safe room. A safe room relies on the entire enclosure, its openings, connections and foundation for its intended hazard. Windows, partial exposure, heavy objects above, flooding and access change the situation. Plan a household refuge now and evaluate any proposed safe-room conversion as a complete design.