Firebase Firestore Integration for App

I need help integrating Firebase Firestore into my already developed app. The main goal is to set up efficient data storage and retrieval.

Key Requirements:
- Integrate Firestore for data storage and retrieval
- Implement email/password user authentication
- Set up the following data types:
- User profiles
- Transaction records
- App settings

Ideal Skills and Experience:
- Strong experience with Firebase Firestore
- Proficient in implementing email/password authentication
- Background in mobile app development and database integration

Please provide examples of similar work done. Looking forward to your bids!