"what customs to look for while performing agencies functions?"?

Answer 1

I would say do your own homework, and at least give some more details if you want a answer.

remember what happens in real life may not be what your study material is saying

. but local or ethnic customs, for example in some cultures you don't speak first to a women or even need to ask the mans permission to speak to a women in his household.
While this is not normal for US people, those that are still living by thier customs will be offended and often hostile if you don't respect thier customs.

Answer 2

Customs of the agency and community.