Excel Data Cleanup Needed

I’m providing a set of Excel and CSV files that are currently cluttered with duplicate rows and a variety of missing or incorrect values. Your job is to give each file a thorough scrub so the data is fully analysis-ready.

You’ll receive the raw spreadsheets along with a short set of validation rules (required columns, acceptable ranges, and a few business-specific checks). Working in Excel, Power Query, Python/pandas, or any other reliable tool of your choice, please remove all duplicates, repair or clearly flag invalid or empty cells, and make sure the overall structure of each sheet stays intact.

Deliverables
• A cleaned version of every spreadsheet (.xlsx or .csv as supplied) with duplicates removed and faulty entries fixed or flagged.
• A concise change log or notes tab summarising what was altered—enough for me to trace the adjustments quickly.

When you reply, highlight the relevant data-cleaning experience you have; no lengthy proposal needed. If you can turn this around within two days, great—otherwise include an accurate timeline so I can plan accordingly.