A full legal or commonly-used name is the minimum I need. A recent photo and birth date sharpen the accuracy of the work considerably, because they help me connect the casting to the correct person with no ambiguity.
If you don't have a birth date, that's fine — a clear photo and full name is usually enough. What I never need is anything invasive or obtained without their knowledge in a way that would make you uncomfortable; a name and photo you already have access to is sufficient.
All details you share stay strictly between us and are used only for the ritual itself.