Financial Transaction Excel Consolidation

I have several Excel files that hold our financial records, each one split out by transaction type. Right now, only the sales transactions need to be brought together, cleaned up and presented in one master workbook that I can trust.

Here is what I need from you:
• Merge every sales-related sheet and file into a single, well-structured master sheet.
• Remove duplicates, fix inconsistent date or currency formats and flag any obvious data gaps so I can trace them quickly.
• Add a simple dashboard or pivot table summary showing total sales, averages and a monthly trend line so I can spot patterns at a glance.

Please keep all formulas transparent and leave a notes tab outlining any assumptions or issues you encounter. Once delivered, the master file should be ready for immediate use in Excel 365 with no broken links or external references.