The fee for the professional service is an essential element of the work contract that is stipulated between the lawyer and his client, therefore it must be paid upon completion of the activity requested by the assisted party. The client, however, is required to advance to the lawyer, the out-of-pocket expenses such as costs of writing, collation, printing, filing, notification, registration in the role, inspections, transcriptions etc., as well as the advances relating to the activity carried out up to that point.