Memoir is a personal legacy written so we can call it a historical source but not document. It is not an evidence, a report or not even a record. It is more like an autobiography or a biography from memorial times. It is a legacy written by a person for a person.
Answer: The answer to first question is yours. In the second one, his is correct.
Modern. Contemporary means living or occurring at the same time.
Managing your money (spending,saving and investing)