Document the version and the status of all the input. The client indicates which input of this list is relevant and indicates the value of these relevant inputs. Documents that (according to the client) have no or low value, may better be ignored than seriously or extensively analyzed.
Objective is to capture versions and status of all input and consolidate this input in terms of relevancy and value.
Part of this task is also to isolate the client objectives and translate them into concrete change drivers.