(cf clause 75A of EP&A Regulation 1994)(1) An application for a complying development certificate:(a) must contain the information, and be accompanied by the documents, specified in Part 2 of Schedule 1, and(b) if the certifying authority so requires, must be in the form approved by that authority, and(c) must be delivered by hand, sent by post or transmitted electronically to the principal office of the council or the accredited certifier, but may not be sent by facsimile transmission.(2) Immediately after it receives an application for a complying development certificate, the council or accredited certifier must endorse the application with the date of its receipt.(3) In determining whether an alteration, enlargement or extension of a BASIX affected building is BASIX affected development, the certifying authority must make its determination by reference to a genuine estimate of the construction costs of the work, including any part of the work that is BASIX excluded development. The estimate must, unless the certifying authority is satisfied that the estimated cost indicated in the application for a complying development certificate is neither genuine nor accurate, be the estimate so indicated.(4) A single application for a complying development certificate may be made for development comprising the concurrent erection of new single storey or two storey dwelling houses if each is to be erected on existing adjoining lots.