Custom Google Spreadsheet for fitness Management

I'm looking for an expert in Google Sheets who can create a tailored spreadsheet for my selling operations. The spreadsheet should include a comprehensive customer database, as well as track fitness-related data.

Key Requirements:
- Design a user-friendly, functional spreadsheet
- Implement a detailed customer database
- Track fitness progress of customers
- Track sales and customer interactions
- Use of advanced Google Sheets functionalities

Ideal Skills:
- Proficient in Google Sheets
- Experience in data management and sales tracking
- Familiarity with fitness-related data
- Excellent attention to detail
- Able to deliver a user-friendly design