Bring the parties responsible for the affected installation into the discussion early. Agree who can authorise changes, who can make equipment accessible and who will receive the completed records. Where the intended arrangement is still being designed, request an assessment of that proposal before asking for a certificate for a finished installation.
After work, the records should make sense to someone who did not manage the project. Retain the relevant property reference, installation description and records of authorised alterations together. A drawing can help explain which boundary is covered, but a hand-drawn sketch does not settle a cadastral dispute or replace the inspection.