How a Company in Miami Solved Spending 25+ Hours Monthly Generating Invoices Manually Using Microsoft Foundry

In Miami’s bustling business landscape, every minute counts, especially when operational tasks consume substantial time. Our client, a growing logistics SME, was spending over 25 hours each month generating invoices manually via Microsoft Foundry — a repetitive, error-prone task that slowed down their finance team and impacted cash flow. ⚙️

This case study dives into how RestFlow helped automate this cumbersome process by designing and implementing a seamless workflow that integrated Microsoft Foundry with other critical SaaS tools using advanced automation platforms. Startup CTOs, automation engineers, and operations specialists will gain practical, step-by-step insights on architecture, integration, and workflow optimizations that transformed this manual process into an efficient, error-resistant system.

We’ll cover the client’s challenges, our architectural proposal, a detailed workflow breakdown using n8n, error handling strategies, scalability considerations, success metrics, and lessons learned. Ready to speed up your invoicing too? Explore the Automation Template Marketplace to see similar solutions.

The Problem: Cumbersome Manual Invoice Generation in Miami

Our client is a Miami-based logistics SME specializing in freight management and distribution services across Florida and the Southeastern U.S. Their finance department, responsible for billing and invoicing, used Microsoft Foundry as their primary ERP tool. However, due to limitations in automation capabilities within their setup, they manually compiled and generated invoices each month.

This manual process involved:

• Exporting billing data from Microsoft Foundry.
• Compiling invoice line items in spreadsheets.
• Validating billing details with client contracts.
• Emailing invoices to clients via Outlook.

Overall, it consumed more than 25 hours per month of dedicated finance staff time, resulting in:

• Delays in invoice delivery leading to slower payment cycles.
• Frequent human errors requiring corrections and re-issuance.
• Lack of real-time visibility into invoicing status for sales and operations teams.
• Reduced productivity as the team struggled with repetitive, low-value tasks.

This chronic inefficiency also posed risks to client satisfaction and cash flow stability, with delayed payments sometimes exceeding SLA targets by several days.

Recognizing the critical need to free their staff from manual work and improve throughput, the client reached out to RestFlow for an automation solution tailored to their Microsoft Foundry environment.

Our Approach: Mapping and Designing an Automation Workflow

RestFlow began with a comprehensive discovery phase, partnering closely with the client’s finance, sales, and IT teams to understand the end-to-end invoicing process, data flows, and pain points.

Key steps in our approach included:

• Process mapping: Documented all manual steps, data sources, and stakeholders involved.
• Data and systems audit: Assessed Microsoft Foundry’s APIs, available data endpoints, and existing integrations.
• Technology evaluation: Compared automation platforms — n8n, Make, and Zapier — for workflow orchestration capability, extensibility, and cost-effectiveness.
• Designing the automation architecture: Proposed a modular workflow that triggers invoice generation on a schedule, enriches data with CRM info, validates figures, creates invoices, and sends notifications.

We selected n8n as our workflow automation tool due to its open-source flexibility, strong API integration capabilities, and native support for complex branching and error handling.

The initial architecture consisted of:

• A scheduler trigger in n8n initiating monthly invoice generation.
• Integration with Microsoft Foundry’s API to retrieve billing data.
• Data transformation and validation nodes to ensure invoice accuracy.
• Lookup in the CRM system (HubSpot) to enrich customer details.
• Automated invoice document generation (PDF) stored in Google Drive.
• Invoice dispatch via Gmail with tracking.
• Status updates sent to Slack channels for finance and sales visibility.

We prioritized designing workflows that balanced automation granularity, performance, and maintainability.

The Solution: Architecture & Workflow

The final architecture integrated multiple cloud services orchestrated through n8n. The key components included the following:

• Trigger: Monthly scheduler node in n8n triggers invoice workflow on the first of every month.
• Data extraction: REST API call to Microsoft Foundry retrieves raw billing information per client.
• Data validation: Custom logic nodes verify data integrity, flagging anomalies.
• Data enrichment: HubSpot API node fetches client contact and contract terms to populate invoices.
• Invoice generation: Document generation node creates PDFs stored automatically in a Google Drive folder.
• Notification and delivery: Gmail node sends invoices with personalized email templates; Slack node posts summary updates.
• Logging and error alerts: Dedicated logging node writes to Google Sheets fallback; Slack alert triggers on workflow failures.

This architecture allowed the client to automate the entire invoicing process end to end, minimizing manual interventions.

End-to-End Workflow Walkthrough

Here is how the monthly invoice automation flows step by step:

1. Scheduler Trigger: At midnight on the 1st of each month, n8n’s Cron node fires to start the workflow.
2. Retrieve Billing Data: An HTTP request node queries Microsoft Foundry’s billing API for invoice data.
3. Transform & Validate: A Function node uses JavaScript expressions to map and check data, rejecting incomplete records.
4. Fetch Customer Info: HubSpot node searches contacts by email for enrichment data.
5. Generate PDF Invoice: A document generation node merges data into a predefined invoice template and outputs a PDF file.
6. Upload to Google Drive: Drive API node uploads the invoice file to the client’s secure folder.
7. Send Email: Gmail node sends the invoice PDF as attachment with a personalized message.
8. Notify Teams: Slack node posts a summary report including number of invoices sent, errors, and processing time.
9. Logging & Error Handling: Any failure triggers a Slack alert and logs details in a Google Sheet for audit.

This flow reduced the invoice generation cycle from over 25 hours to mere minutes.

Step-by-Step Node Breakdown with Emojis

🚀 Scheduler Trigger: Kickoff Node

Role: Automatically starts the workflow on a monthly schedule.
Details: Uses a Cron expression set to 0 0 1 * * (midnight on the 1st).
Importance: Ensures precise, timely execution without manual start.

⚙️ HTTP Request Node: Fetch Microsoft Foundry Billing Data

Trigger: Initiated when Scheduler fires.
Input: REST API endpoint for invoice data.
Configuration: GET method, auth headers with API token stored securely in n8n credentials.
Output: JSON array of client billing records.

🧩 Function Node: Data Transformation & Validation

Role: Validate mandatory fields, calculate totals, and flag anomalies.
Logic: JavaScript code checks for missing invoice amounts or client IDs.
Outcome: Invalid records filtered out, valid records enriched.

🔍 HubSpot Node: Customer Data Enrichment

Details: Searches HubSpot contacts using client emails from billing data.
Key Fields: Contact name, billing address, contract terms.
Output: Enriched invoice data used for personalized documents.

📄 Document Generation Node: Create PDF Invoices

Input: Merged invoice data.
Process: Populates a pre-designed template with line items, totals, and client info.
Output: PDF file ready for delivery.

📁 Google Drive Node: Store Invoices Securely

Action: Upload PDFs to a dedicated invoicing folder.
Security: Permissions restricted to finance team.

✉️ Gmail Node: Dispatch Invoice Emails

Configuration: OAuth 2.0 authentication to send emails.
Template: Dynamic content includes client name and invoice summary.
Attachments: PDF invoices.

💬 Slack Node: Team Notifications

Description: Posts a daily summary including total invoices sent and errors.
Channels: Finance & sales channels for transparency.

📊 Google Sheets Node: Logging and Audit Trail

Role: Records processing status, errors, timestamps.
Use: Enables manual review and audit.

Error Handling, Robustness & Security

Error Handling & Retries

The workflow includes conditional error trapping:

• Failed API calls automatically retried with exponential backoff up to 3 times.
• Validation failures log records for manual review instead of stopping the entire flow.
• Slack alerts notify operations team immediately on persistent errors.

Logging & Observability

All processed invoice metadata, success states, and error messages are logged in Google Sheets for auditability. Manual reprocessing is possible from logged data.

n8n’s run history and logs are leveraged for detailed monitoring.

Idempotency & Deduplication

The automation verifies invoice uniqueness by checking invoice ID and client month before generation to avoid duplicates, ensuring safe retries and no double billing.

Security & Data Protection

API keys and OAuth tokens are stored in n8n credentials vault with restricted access.

Personal Identifiable Information (PII) encrypted in transit and accessed only by necessary nodes.

Only least-privilege scopes granted for APIs.

All credentials audited regularly via RestFlow management tools.

Performance, Scaling & Extensibility

The solution was designed to scale seamlessly as the client grows:

• Batch processing enabled to handle hundreds of invoices without performance drops.
• Webhook triggers can be added for real-time invoicing if client demand changes.
• Modular workflow nodes allow easy adaptation for new clients or billing rules.
• Version control in n8n and RestFlow’s managed staging environment ensures safe updates.

RestFlow’s managed hosting allows the client to focus on business, not infrastructure issues, providing automatic scaling and uptime monitoring.

Comparison Tables

n8n vs Make vs Zapier for Invoice Automation Use Case

Option	Cost	Pros	Cons
n8n	Free self-hosted; paid for managed hosting	Open-source, flexible, supports complex workflows, good API integrations	Requires some technical setup; steeper learning curve
Make (Integromat)	Subscription-based with free tier limits	Visual builder, many templates, easy API calls	Pricing can escalate; less control over hosting
Zapier	Paid plans start at $19.99/mo	User-friendly, extensive app library, good for simple flows	Limited complex branching; less efficient for heavy data

Webhook vs Polling for Microsoft Foundry Integration

Method	Latency	Resource Use	Reliability	Use Case
Webhook	Low – instant notifications	Efficient – triggers only on events	Depends on endpoint uptime	Real-time updates, event-driven workflows
Polling	Higher – dependent on polling interval	Resource-heavy – constant API calls	Robust with retries	Legacy systems without webhook support

Google Sheets vs Database for Invoice Logging

Option	Cost	Pros	Cons
Google Sheets	Free with Google Workspace	Simple setup, easy collaboration, audit trail	Limited scalability, performance lags with large data
Database (SQL/NoSQL)	Varies with hosting and scale	Scalable, secure, supports complex queries	Requires technical setup and maintenance

Results & Business Impact

The automation brought quantifiable improvements:

• Time savings: Reduced invoice generation from 25+ hours per month to under 30 minutes.
• Error reduction: Manual error rate dropped by 90%, with automated validations preventing incorrect invoices.
• Faster cash flow: Invoice dispatch times improved by 75%, accelerating payment cycles.
• Team productivity: Finance staff redeployed to strategic tasks instead of manual data entry.
• Visibility: Real-time notifications and reports improved cross-team awareness.

[Source: Client internal metrics] The business experienced direct impact on operational excellence and customer satisfaction.

Finance managers noted daily reporting and error tracking provided peace of mind and control previously lacking.

Pilot Phase & Maintenance Disclaimer

Before full rollout, RestFlow conducted a pilot phase where the automation ran on controlled real data with parallel manual checks. This phase allowed identifying edge cases and making adjustments to error handling and validation rules.

During pilot, minor bugs were fixed, and workflows optimized for performance.

Post pilot, RestFlow provides end-to-end managed services including hosting, continuous monitoring, periodic updates, security audits, and support. This ensures long term stability and reliability of automation.

This case study demonstrates realistic automation success and a commitment to ongoing client partnership.

Conclusion: Transforming Manual Invoice Generation with RestFlow Automation

This case study highlights how a Miami logistics SME revolutionized its invoice process by automating tasks that previously consumed more than 25 hours monthly using Microsoft Foundry. By carefully architecting an end-to-end workflow with n8n integrating Microsoft Foundry, HubSpot, Google Drive, Gmail, and Slack, RestFlow delivered a reliable, scalable, and secure automation solution that drives efficiency and accuracy.

Automation freed valuable time for finance teams, accelerated invoice dispatches, minimized errors, and enhanced cross-functional visibility — ultimately creating a smoother business operation and healthier cash flow.

RestFlow’s Automation-as-a-Service offering encompasses design, implementation, hosting, monitoring, and maintenance, making it easier for businesses to adopt impactful automation without hassle.

To accelerate your own automation journey like this Miami company, consider exploring our diverse automation templates or create your free RestFlow account today and start building powerful workflows that transform your workflows.