Why Closing Disclosure Extraction Requires Regulation-Anchored Schema Design

A Closing Disclosure is a federally regulated mortgage form introduced by the Consumer Financial Protection Bureau under Regulation Z, with a fixed layout that makes structure inference unnecessary and unreliable. Because every section of closing costs is assigned a stable letter designation, extraction pipelines can anchor to those letters rather than searching for fee names, enabling checkable subtotals and meaningful detection of empty sections. The critical challenge lies in the closing cost details page, where each line item can carry up to five distinct amounts across borrower, seller, and third-party payment columns. A schema that captures only one amount per line will silently misattribute costs — for example, recording a seller-paid title premium as borrower-paid — and because totals are extracted rather than derived, the errors go undetected. The correct data model maps each line item to a column-keyed amount structure tied to its lettered section, allowing totals to be independently verified against their printed subtotals.