Square POS + 1C Inventory Integration

Project Overview
We are a retail grocery business in Canada operating multiple store locations using Square POS and 1C (1С) for accounting and inventory.
We need an experienced developer to build a reliable two-way integration between Square and 1C.
Main Goals
Multi-location inventory management
Each store must have its own warehouse
Inventory must sync correctly per location
Accurate real-time or near real-time synchronization
Required Functionality
Product synchronization:
SKU
Barcode
Name
Categories
Pricing
Inventory synchronization per location:
Goods receiving in 1C must update correct Square location
Write-offs must sync
Store-to-store transfers must sync properly
Sales in Square must update inventory in 1C
Logging & error handling:
Sync logs
Error tracking
Manual re-sync option
Technical Expectations
Experience with Square API
Experience integrating with 1C
REST API knowledge
Webhooks implementat...