Senior n8n API Developer for Car Rental Voice AI Workflow — GoHighLevel, Webhooks, REST APIs

I’m looking for a senior n8n/API automation developer to help fix and complete a production AI voice workflow for a car rental business. This is not a simple chatbot project. The workflow connects a GoHighLevel Voice AI agent to n8n, then uses webhooks, REST APIs, JSON mapping, and business logic to check availability, calculate rental rules, and help process bookings. The work includes: * Auditing the current GoHighLevel and n8n workflow * Finding where webhook data is coming from * Mapping the full data flow * Fixing or rebuilding broken webhook/API handoffs * Applying car rental business rules * Handling dates, pickup/dropoff times, rental categories, availability, pricing, mileage, and cancellation rules * Returning clean structured responses back to the voice agent * Adding error handling, logs, and test cases before production Required skills: * n8n workflows * REST API integrations * Webhooks * JSON mapping * JavaScript Code nodes * Postman or similar API testing * Debugging production workflows * GoHighLevel workflows or ability to learn fast * AI voice agent/tool-call experience is a strong plus Please do not apply if you only build basic chatbots or simple Zapier/Make automations. In your proposal, answer these questions: 1. Describe a real n8n workflow you built where a webhook received data, called an external API, applied business logic, and returned a structured response. 2. How would you trace where webhook data is coming from if the source is unclear? 3. How do you handle API failures, missing fields, bad dates, and bad responses? 4. Have you worked with GoHighLevel or voice AI agents? If yes, explain exactly what you built. 5. What would your first 2 hours of audit look like? First step will be a paid audit/test task, not a full rebuild.