I need a straightforward Excel-based tool that lets me enter a loan amount, annual interest rate, repayment period, and start date, then instantly produces a clear amortisation schedule. The focus is on simple input and output—no macros with complex buttons or external integrations—so everyday users can type figures into highlighted cells and view results immediately. Core requirements • Automatically break each payment into principal and interest for monthly instalments. • Flag any late payments and apply a daily late-interest rate I can adjust in one cell. • Support both personal and business loans, with room to label each loan for tracking. • Allow quick edits to the rate, term, or outstanding balance and recalculate on the spot. • Summarise totals paid, interest accrued, and remaining balance at the top of the sheet. I expect clean, well-commented formulas (or lightweight VBA if absolutely necessary), organised worksheets, and clear cell protections so users can’t accidentally overwrite the logic. If the first version runs smoothly, I’ll likely tap you for enhancements such as printable reports or additional loan types.