GPT 4.1-mini automated proposal to payment lifecycle management
Ready for 3.0Ready for 3.0. This template uses no nodes that n8n 3.0 removes. No removed nodes, versions or helpers found. Static check, last run 2026-10-19.
What this workflow does
This AI workflow has 33 nodes and runs when someone submits an n8n form (“Proposal Request Form”) (plus 1 other trigger). Along the way it connects OpenAI Chat Model and Gmail.
How it runs
Trigger: When someone submits an n8n form (“Proposal Request Form”) (plus 1 other trigger).
- Workflow Configuration (Edit Fields (Set)): sets 4 fields: approverEmail, crmApiUrl, taskManagementApiUrl…
- Get Pending Invoices (Data table): get
- Store Proposal Request (Data table): uses Data table
- Check Payment Status (Code): runs custom JavaScript code
- Generate Proposal (AI Agent): runs an AI agent, with model: OpenAI Chat Model; output parser: Proposal Output Parser
- Check If Payment Overdue (If): checks a condition and branches into true / false
- Store Generated Proposal (Data table): uses Data table
- Send Payment Reminder (Gmail): uses Gmail
- Send Proposal for Approval (Gmail): uses Gmail
- Update CRM (HTTP Request): calls an HTTP API (POST)
…plus 13 more steps. See the full node list below.
Services it uses
Before you upgrade to n8n 3.0
Nothing in this workflow is removed in n8n 3.0, so it should import and run after the upgrade.
Nodes used (12)
- n8n Form Trigger
n8n-nodes-base.formTrigger - Edit Fields (Set)
n8n-nodes-base.set - Data table
n8n-nodes-base.dataTable - AI Agent
@n8n/n8n-nodes-langchain.agent - OpenAI Chat Model
@n8n/n8n-nodes-langchain.lmChatOpenAi - Structured Output Parser
@n8n/n8n-nodes-langchain.outputParserStructured - Gmail
n8n-nodes-base.gmail - Wait
n8n-nodes-base.wait - If
n8n-nodes-base.if - Schedule Trigger
n8n-nodes-base.scheduleTrigger - Code
n8n-nodes-base.code - HTTP Request
n8n-nodes-base.httpRequest
From the author
How It Works This workflow automates end-to-end contract and invoice management using AI intelligence. It processes proposals through intelligent contract generation, approval workflows, and automated invoicing. OpenAI analyzes proposal content while the…