3D Dog Customization System for Mobile App

I am building a mobile app and need a developer to create a 3D dog customization system similar to Rocket League’s car customization.

Core Requirements:

* A 3D dog character (already created in GLB format)
* Ability to equip items:

* Hats
* Collars
* Skins / colors
* Accessories
* Items must support rarity tiers:

* Common
* Rare
* Very Rare
* Exotic

Features Needed:

* Character viewer (rotate, zoom)
* Equip/unequip items visually in real-time
* Store system:

* Display items by rarity
* Purchase/unlock items
* Inventory system:

* Save owned items per user
* Backend integration (Firebase or API)

Technical Options (open to recommendation):

* Unity (preferred for performance and flexibility)
* OR Web-based (Three.js) embedded in app via WebView

Important:

* The system must be optimized for mobile performance
* Clean architecture so I can expand later (e.g. animations, upgrades)

Bonus:

* Experience with game systems (inventory, cosmetics)
* Experience with monetization systems

Please include:

* Examples of similar work (character systems or 3D apps)
* Recommended tech stack
* Timeline and cost estimate