Excel Loan Calculator Development/Fix

I'm looking for an expert in Excel to create or fix a loan calculator for me. The calculator should take various loan parameters and compute different outputs.

Specific Parameters:
- Loan amount
- Loan term
- Fixed interest rate
- Fees
- Prepayments

Calculations Required:
- Monthly repayment amounts
- Total interest paid
- APR calculation
- Total amount paid

Additional Input Options:
- Fees
- Prepayments
- Grace period

Ideal skills for this project include advanced Excel proficiency and experience with financial modeling. Please bid only if you can deliver a professional and accurate tool.