Flutter Firebase CRM App

I need a production-ready Flutter Android application backed by Firebase (Firestore + Auth) that functions as a compact CRM for tracking enquiries and disciplined follow-ups.
Core features:
• Enquiry form with dependent dropdown logic (e.g., category → model)
• Conditional fields (exchange toggle reveals model & value)
• Expected purchase date and next follow-up date logic
• Status workflow: Interested, Follow-up Needed, Purchased, Competition, Not Interested
• Next follow-up date mandatory for Interested and Follow-up Needed
• Priority tag (Hot/Casual)
• Auto timestamp, source, and owner tracking
All enquiries stored in Cloud Firestore.
Follow-up dashboard must support filters: • Today
• Overdue
• Upcoming
• Custom date range
Authentication: • Phone OTP via Firebase Auth
• Role-based Firestore security rules
Admin: full access
Staff: access only to their own enquiries
Android-only build.
Tapping phone number must launch native dialer and return to app.
Deliverables: • Well-commented Flutter source code
• Firebase configuration
• Firestore security rules
• Signed release APK
• README (setup, build, role configuration)
• 60–90 days bug-fix support
Expected timeline: 15–20 days.
I will test by running flutter run, installing the APK, validating OTP login, verifying role restrictions, confirming dropdown dependencies, and checking date-based filtering.