We might not need all of this every time, but here’s the usual line-up:
A full breakdown of what happened.
Any extra info we ask for to recover costs from other parties.
Details of any other insurance covering the same event.
Any related correspondence (e.g., court papers).
Additionally for Motor claims specifically:
Accident report and SAPS case number.
Third-party contact details.
Photos of your reg disk and the other driver’s reg disk.
Pics of the accident scene, all vehicle damage, and the other vehicle.
A sketch of the accident scene (yes, even if your drawing skills are… limited).