Supply assessment
Duplicates gone before you ever see them.
Work is scoped against what the sources can actually support. Gaps are measured and reported, not interpolated. Sometimes the honest finding is that no such audience exists, and that gets said.
Handover walkthrough
Going through the file, its columns and its limits with whoever will use it.
Jurisdiction split
Separating records by the rules that apply where the person is, not where the file was built.
Exclusion log
A record of what was removed and why, delivered alongside the file it came out of.