Excel Macro for Price Updates

I need an Excel macro to update cost and retail prices from various pet stores and distributors. The price data will be provided in Excel files from different sources, and updates should be scheduled at specific times.

Requirements:
- Write an Excel macro for price updates
- Integrate data from multiple Excel files
- Enable scheduled updates at specified times

Ideal Skills:
- Proficiency in Excel and macro development
- Experience with data integration from multiple sources
- Strong scheduling and automation skills

Please provide examples of similar work done.