Configuring Aging Id at customer level
PeopleBooks says that "The Aging process uses the aging ID assigned to the business unit to age items unless you override it for individual customers. The aging reports use the aging ID that you enter on the run control page to age the items on the reports."
Where in Customer module can a user configure the Aging Id to override the business unit Aging ID options.
Answer:
Right now there is no place where Aging Id can be defined at customer level.
An Enhancement request Bug 11650933 ( PROVISION TO DEFINE AGIND ID AT CUSTOMER LEVEL) has been created for the development to fix this issue. The development team will consider to incorporate this change in future release.