Complex WordPress/WooCommerce Debug & Fix

Our long-running WooCommerce store has drifted into a tangle of problems—pages built with Elementor sometimes render half-broken, orders randomly fail, the database occasionally spikes to 100 % CPU, and server logs show intermittent 500 errors that no one has traced to a single culprit... (Budget: $10 - $30 USD, Jobs: Debugging, Elementor, MySQL, Nginx, PHP, Website Optimization, WordPress)