 2019  Contract number: [ complete ]  II.21.5  Pre-financing, performance and money retention guarantees  II.21.6  Interim payments and payment of the balance  (c) the party causing repetition of the transfer bears the costs for repeated transfer.  (a) the financial guarantee is provided by a bank or a financial institution approved by the  contracting authority or, at the request of the contractor and with the agreement of the  contracting authority, by a third party;  (b) the guarantor stands as first-call guarantor and does not require the contracting authority  to have recourse against the principal debtor (the contractor).  If, as provided for in Article I.6 , a financial guarantee is required for the payment of pre- financing, as performance guarantee or as retention money guarantee, it must fulfil the  following conditions: The contractor bears the cost of providing such guarantee.  Pre-financing guarantees must remain in force until the pre-financing is cleared against interim  payments or payment of the balance. Where the payment of the balance takes the form of a  debit note, the pre-financing guarantee must remain in force for three months after the debit  note is sent to the contractor. The contracting authority must release the guarantee within the  following month. Performance guarantees cover compliance with substantial contractual obligations until the  contracting authority has given its final approval for the service. The performance guarantee  must not exceed 10 % of the total price of the specific contract. The contracting authority must  release the guarantee fully after final approval of the service, as provided for in the specific  contract. Retention money guarantees cover full delivery of the service in accordance with the specific  contract including during the contract liability period and until its final approval by the  contracting authority. The retention money guarantee must not exceed 10 % of the total price  of the specific contract. The contracting authority must release the guarantee after the expiry of  the contract liability period as provided for in the specific contract.  The contracting authority must not request a retention money guarantee for a specific contract  where it has requested a performance guarantee. The contractor (or leader in the case of a joint tender) must send an invoice for interim payment,  as provided for in Article I.6 or in the tender specifications or in the specific contract. The contractor (or leader in the case of a joint tender) must send an invoice for payment of the  balance within 60 days of the end of the period of provision of the services, as provided for in  Article I.6, in the tender specifications or in the specific contract. Payment of the invoice and approval of documents does not imply recognition of the regularity,  authenticity, completeness and correctness of the declarations and information they contain. Payment of the balance may take the form of recovery. 35 