For costs related to your approval, please refer to the tables sorted by application type that are provided in the Annex of the EASA fees and charges regulation Commission Regulation (EU) No 319/2014. Please review especially table 10 of the Fees & Charges Regulation (Commission Regulation (EU) 319/2014). The table explaining how we practically determine chargeable courses and sites is also available in the FAQ section C.4.5 of the Fees and Charges regulation
Please note that the fees are subject to an annual inflation rate and do not include the travel costs associated to on-site audits (flight & train tickets, accommodation and travel hours -which are charged on an hourly rate basis- etc...). These will be charged separately.