Calendar Scheduler Integration with Dual Availability (2-Person Combined Booking)

Project Title:
Calendar Scheduler with Dual Availability Integration

Description:

Hello,

I need a developer to integrate an appointment booking system into my website where booking is allowed only when two users are available at the same time.

Key Requirements:

Combine two calendars and show only common available slots
Booking allowed only when both persons are free
Integration with Google Calendar (preferred) or Microsoft Outlook
Email notifications and reminders
Simple and user-friendly interface

Deliverables:

Fully working scheduler
Bug-free implementation

Please share similar work if available.