(a) Except as provided in subsection (b), the Register of Wills may demand and receive in advance for services performed by him such fees as shall be set by the court having jurisdiction over probate matters in the District of Columbia.
(b) Where the estate does not exceed $500 in value the Register of Wills shall receive no fees, and where the estate does not exceed $2,500 in value the fees may not exceed $15.