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Sales Infrastructure

The $43/mo Cold Email Stack That Outperforms $500/mo Tools

Custom Sending Platform | Lead Enrichment Pipeline

The Problem

Cold email tools like Instantly, Lemlist, and Apollo charge $97-497/month. They bundle everything together: sending, warm-up, sequences, analytics. Sounds convenient.

But here's what nobody tells you:

Except for one thing: warm-up.

"Sending cold emails is easy. A/B testing is easy. Sequences are easy. But warming up accounts? That requires a network of real inboxes exchanging emails, opening them, marking them as not-spam. Building that yourself is a nightmare."

That's the insight that shaped our entire approach.

The Secret

We use Instantly—but only their cheapest tier at $37/month. And we use it for exactly one thing: indefinite account warm-up.

Warm-up is the hardest thing to automate properly. You need a network of real accounts interacting with your emails, marking them as important, replying to them. Instantly has built that network. We're happy to pay $37/month for it.

Everything else? We built it ourselves.

Why pay $497/month for features any developer can build in a day?

The Approach: Our 5-Step Pipeline

Here's exactly what we built:

Lead Scraping with Apify

We use Apify to scrape leads from LinkedIn, directories, job boards, and other sources. Custom actors for each source type, outputting clean JSON.

Email Validation

Before any email touches our sending accounts, we validate it. Catches invalid addresses, spam traps, and catch-alls. Protects domain reputation.

AI-Driven Enrichment

Agent-driven scrapers enrich each lead with company data, tech stack, recent news, and generate personalization angles. The AI finds the hook that makes each email relevant.

Custom Sending Platform

Our own cold email tool handles everything: A/B testing, multi-account rotation, reply detection via IMAP, and automated sequences. SQLite for state. No external dependencies.

Warm-up via Instantly

Instantly's $37/month tier keeps our accounts warm indefinitely. We don't use it for sending—just warm-up. That's the only thing worth paying for.

The Stack

What We Don't Use

  • Instantly for sending ($97-497/mo)
  • Apollo for leads ($99-499/mo)
  • ZoomInfo for enrichment ($$$)
  • Lemlist for sequences ($99/mo)
  • 5k/month send limits

What We Built

  • Apify for scraping (pay-per-use)
  • Custom validation pipeline
  • AI enrichment agents
  • Self-hosted sending platform
  • Instantly only for warm-up ($37/mo)

Email Infrastructure

The secret to high-volume sending without breaking the bank:

freestantly/ ├── config/ │ ├── accounts.json # SMTP credentials (6 Zoho accounts) │ └── domains.json # Domain rotation config ├── tools/ │ ├── sender.py # Multi-account sending with A/B │ ├── monitor.py # IMAP reply detection │ ├── tracker.py # Open/click tracking │ └── followup.py # Automated sequences ├── enrichment/ │ ├── scraper.py # Apify integration │ ├── validator.py # Email validation │ └── ai_enrich.py # AI personalization ├── data/campaign.db # SQLite state └── templates/sequences.md # Email copy

Our Sending Features

A/B Testing

Test subject lines, opening lines, CTAs. Track which variants convert.

Multi-Account Rotation

6 accounts across 2 domains. Automatic load balancing.

Reply Detection

IMAP monitoring catches responses. Auto-pauses sequences on reply.

Sequence Automation

Multi-step follow-up sequences with configurable delays.

Open/Click Tracking

Know which emails get engagement. Pixel and link tracking.

No Send Limits

Scale beyond 5k/month. Limited only by your email accounts.

The Result

$500+
Typical monthly cost
~$43
Our stack
Instantly (warm-up only, cheapest tier) $37/mo
Zoho Mail (6 accounts @ $1/mo) $6/mo
Apify (pay-per-use scraping) ~$0-20/mo
Self-hosted sending platform $0
Total ~$43-63/mo

Same features as tools charging $500/month. No arbitrary send limits. Full control over our data. And we can scale by just adding more $1/month Zoho accounts.

Why This Works

The cold email SaaS market bundles everything together because most users want convenience. But bundling means you're paying for:

The only genuinely hard problem is warm-up. So we pay for that—and only that.

Everything else is just Python scripts, a database, and some email accounts.

The takeaway: Instantly is great for warm-up. But you don't need to pay $97-497/mo for sending when you can build that yourself.

Separate the concerns. Pay only for what's actually hard.

Want This Pipeline for Your Business?

We can build and customize this entire stack for your specific ICP and outreach workflow.

Book a Call