EC - FWC services Dec 2018  Contract no: [complete]  obligations without requiring that the contracting authority has recourse against the principal  debtor (the contractor).  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. The contracting authority may suspend the payment periods specified in Article I.6 at any time by  notifying  the contractor (or leader in the case of a joint tender) that its invoice cannot be processed. The  reasons the contracting authority may cite for not being able to process an invoice are:  The contracting authority must  notify  the contractor (or leader in the case of joint tender) as soon as  possible of any such suspension, giving the reasons for it. In cases b) and c) referred above, the  contracting authority shall notify the contractor (or leader in case of a joint tender) the time limits to  submit additional information or corrections or a new version of the documents or deliverables if the  contracting authority requires it.  a) because it does not comply with the FWC;  b) because the contractor has not produced the appropriate documents or deliverables; or c)  because the contracting authority has observations on the documents or deliverables submitted  with the invoice. 32 II.21.7. Suspension of the time allowed for payment  II.21.6. Interim payments and payment of the balance 