14. An authority may determine a fee in respect of the attendance by authorised registrars at approved places and any such fee shall–
(a)not exceed the amount which reasonably represents the costs incurred or to be incurred directly or indirectly by the local registration authority in respect of that attendance; and
(b)be payable to the local registration authority by the persons to be married not less than 7 days, or such lesser period at the local registration authority’s discretion, prior to the solemnisation of the marriage.