Integrate FB SDK for Item Trading in Unity Game

I'm looking for an experienced Unity developer who can seamlessly integrate the Facebook SDK into my game. The primary function of this integration will be to enable players to trade powerups and items directly with their friends on the platform.

Key Requirements:
- Implementing a manual invitation system for item trading
- Ensuring smooth and user-friendly trading interface
- Maintaining game balance and fairness post-integration

Ideal Skills:
- Proficiency in Unity
- Prior experience with FB SDK integration
- Strong understanding of game design and balance