It depends on various factors, especially the complexity of KPIs in the model & reports, on the region(s) the organization is active and indirectly the size of the organization. It is not a flat fee but ranges from 5k EUR to 25k EUR in majority.
An external audit & certification of the impact KPIs sold in our Impact Credit system is necessary, as is all about trust and authenticity in the reported data. That's what the issuers sell and that's what the buyers use, when communicating about the projects they've supported by buying these Credits. Without this anchor of trust, the intrinsic value of the Credits is not proven.