Smart Invoice Collection System with GPT-4.1, Gmail & Google Sheets

Smart Invoice Collection System with OpenAI, Gmail & Google Sheets Categories: Financial Automation, AI Business Tools, Cash Flow Management This workflow creates an intelligent invoice collection system that automatically follows up on overdue invoices using AI-powered personalization. The system monitors your invoice database, analyzes email history to prevent inappropriate follow-ups, and sends increasingly urgent but professional reminders at precise intervals. Built to solve one of the biggest cash flow killers for small businesses, this automation can easily generate an additional $10-15K per year in recovered payments. Benefits Automated Cash Flow Recovery - Generate $10-15K annually

Help me set up the n8n workflow "Smart Invoice Collection System with GPT-4.1, Gmail & Google Sheets" (https://n8n.io/workflows/5391). It uses: Google Sheets, Gmail, OpenAI. Import the template JSON into my n8n instance, list every credential I need to create, and walk me through testing it.