Eligibility for the services of the Office of the Public Defender shall be determined on the basis of the need of the defendant. Need shall be measured according to:
In the event that a determination of eligibility cannot be made before the time when the first services are to be rendered, or if an initial determination is found to be erroneous, the office shall undertake the same provisionally, and if it shall subsequently be determined that the defendant is ineligible it shall so inform the defendant, and the defendant shall thereupon be obliged to engage his own counsel and to reimburse the office for the cost of the services rendered to that time.
N.J.S. § 2A:158A-14