Challenges in project financing modeling often arise when using a model to develop terms of the loan agreement and other contract structures. Issues that require careful structuring and programming to keep project finance models flexible include sculpting debt repayments, financing the funding requirements during construction, refinancing, credit enhancements, and reserve accounts. Reasons of circular reference logic arising from sculpting and taxes and funding need to be fully understood before they can be solved without copy and paste macros that can ruin a model.

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