Record-keeping obligations require registered persons to maintain accounts, face audit obligations and tax determination if supplies go unaccounted. Every registered person must maintain accurate accounts at the principal place of business covering production, supplies, stock, input tax credit and output tax; records may be electronic. Warehouse operators and transporters must keep consignor/consignee details. The Commissioner can require additional accounts or permit alternative record keeping for classes of taxpayers. Persons above the prescribed turnover must obtain an audit and submit audited accounts and reconciliation statements. Failure to account for supplies permits the proper officer to determine tax as if supplies occurred and to apply the tax determination provisions mutatis mutandis.