Core identifying details and current state of the project.
Client sign-off dates for each stage of the build.
Deliverables and reference material for the engagement.
Where the site lives and how it's served.
Login credentials or references (use a vault, not plain text).
Where the content came from and who supplied contact details.
Policy documentation status for compliance pages.
Payment and shipping configuration (leave blank if not applicable).
Ongoing support window after go-live.