(76)In accordance with the overarching obligation to act in accordance with the best interest of clients and taking into account the obligations resulting from specific Union legislation regulating certain financial instruments (in particular, units in collective investment undertakings and packaged retail and insurance-based investment products (PRIIPs) investment firms should disclose and aggregate all costs and charges, including the costs of the financial instrument, in all cases where investment firms are obliged to provide the client with information about the costs of a financial instrument in accordance with Union legislation.