Fix Shopify & WooCommerce Errors

I run a store that lives on both Shopify and WooCommerce, and right now the two ecosystems aren’t playing nicely together. The Buy-Now and standard checkout buttons tied to the official WooCommerce-for-Shopify app are mis-configured, and a couple of third-party plugins are throwing errors that ripple through to payments and inventory sync.

I need someone who already feels at home in Liquid, PHP, and the Shopify/Woo REST APIs to jump in, trace the conflicts, and restore a fully working flow. Core objectives:

• Eliminate the plugin and app errors so neither platform logs PHP warnings or Liquid exceptions.
• Re-configure the WooCommerce app settings inside Shopify so Buy-Now and full checkout work end-to-end, including taxes, coupons, and shipping rates.
• Fix the current syncing problem: product data, inventory counts, and order statuses must match in real time between dashboards.
• Leave me with clear notes (or light Loom walkthrough) on any code edits, custom hooks, or webhook subscriptions you touch so future updates don’t break again.

I can give admin access to both dashboards plus staging copies of the themes. Production downtime has to be minimal, so please outline how you’ll test changes safely before pushing live.