Not every cost caused by the disaster is eligible. FEMA looks at cost last, after the applicant, facility and work are found eligible, and every cost must pass six tests. You must also keep all records for three years after the final expenditure is documented.
To be eligible, a cost must be:
Keep cost, financial, procurement, property, equipment and program records for three years from the date the final expenditure is documented. If litigation, an audit or another claim starts before then, keep them until it is resolved.
Records retention runs from the final expenditure, not the disaster date. Large projects can stay open for years, so set retention by project, not by incident.