What does a lead actually cost once I am past the test volume?

$122 in the largest split test on record. Across 16,434 postcards in Kansas City, pen and ink cards produced leads at $122 each against $214 for the competing vendor mailing the same market, or 42% cheaper per lead. That was a real estate campaign rather than a plumbing one, so read it as what clean targeting and a real pen can do, not a number to bank on for your zip code.

Is the writing my handwriting, or a font?

Neither. A robot holds a real pen and writes each card in actual ink, on both sides, so the strokes vary the way a person's do and the ink sits in the cardstock. It is not your handwriting and it is not a handwriting font run through a laser printer. Those font versions are why plenty of plumbers already believe handwritten mail does not work. Homeowners spot them.

What if the test produces one call and it is a $180 drain clear?

Then it paid for itself and taught you almost nothing. One call at this size sits inside the range you would get by chance, so it cannot tell you the list works. What it does tell you is that the message got somebody to pick up the phone, which is the part most cards fail at entirely. Treat a single call as permission to run the test bigger.

Does every card get a QR code if my customers just call the number?

Yes, and keep it even though plumbing customers overwhelmingly call. Each card carries its own QR code, which is the easiest way for a homeowner to get your number into their phone instead of hunting for the card six months later. A scan also identifies the exact address, so you learn which streets are live even when the caller never thinks to mention the card.

How low does the per card price go?

$1.10 per card at 5,000 pieces. Orders of 1,000 to 4,999 run $1.20, and smaller orders are $1.35. There is no monthly platform fee at any volume, which is what changes the math against competitors charging $199 to $550 a month before they write a single card. At 300 cards a month, a $550 subscription costs more than the postcards do.

The $67 Marketing Test Every Plumber Should Try This Month

You're One $67 Test Away From Your Best Marketing Channel

Every plumber I talk to wants the same thing: more calls from homeowners who are ready to pay and aren't shopping three competitors.

The usual answer is "spend more on Google Ads." That means $29 per click and $144 per lead to compete with every other plumber bidding on the same keywords.

Here's a better first step: spend $67 on 50 handwritten postcards and see what happens.

That's not a typo. Fifty postcards. Sixty-seven dollars. One neighborhood. Real data in 2-3 weeks.

What Does the $67 Setup Look Like?

Step 1: Pick 50 Addresses (15 minutes)

Choose a neighborhood where you've done work before. Ideally within 3-5 miles of your base. Pull 50 owner-occupied single-family homes.

Good sources for addresses:

Your past job records (nearby homes you haven't served)
County assessor data (free online in most areas)
Google Maps (walk the streets virtually, note addresses)

If you've completed a recent job on Oak Street, grab 50 addresses on Oak, Elm, Maple, and the surrounding streets.

Step 2: Write Your Message (10 minutes)

Don't overthink this. Here's a template:

"Hi [Name], I'm [Your Name], a plumber here in [neighborhood]. I just finished a job on [nearby street] and wanted to introduce myself to a few neighbors.

If you've got anything plumbing-related you've been putting off (a drip, a slow drain, a water heater that's getting old), I'm right around the corner. Happy to take a quick look.

[Phone]

- [Your Name]"

Short. Personal. Not salesy. References a real job on a real street.

Step 3: Send Handwritten (5 minutes)

Upload your 50 addresses and message to Mailbots. We write each card with a robotic pen using real ink on cardstock. Per-piece delivery tracking tells you when each card hits the mailbox.

Cost: 50 cards x $1.35 = $67.50

Include your phone number prominently. Plumbing customers call. They don't fill out web forms.

Step 4: Wait 2-3 Weeks

Cards ship within a few days and USPS delivers within 3-7 business days. Most responses come within 1-2 weeks of delivery.

What Should You Expect From 50 Cards?

Let's be straight about the math. 50 cards is a small sample. Here's the realistic range:

Conservative (1% response): 0-1 calls. At 50 cards, 1% is 0.5, so you might get zero. Don't panic. Small sample sizes have high variance.

Average (1.89% response): 1 call. That's one lead at a cost of $67.50.

Strong (3%+ response): 2 calls. Two leads for $67.50 is $33.75 per lead.

For context, a single Google Ads lead costs $144 on average. Even one response from your $67 test puts you ahead.

And here's the kicker: that one response is a phone call from a homeowner who lives 5 minutes from your last job, isn't comparing you to three other plumbers, and already feels like they "know" you because you wrote them a personal card.

Customers who call by phone are 3x more likely to become paying customers. The close rate on this type of lead is 40-53%.

One call that converts to a $700 job = 10.4x return on your $67 test.

How Do You Know If It Worked?

It worked if: You got 1+ calls from the postcards. That validates the channel and the targeting. Scale to 200-500 cards.

It might have worked if: You got 0 calls but cards were delivered (check tracking). With 50 cards, a 0% response rate is statistically possible even if the true response rate is 2%. Try again with 100-200 cards for a more reliable sample.

It didn't work if: You sent 200+ cards with good targeting and got zero responses. Re-evaluate your message, targeting, or neighborhood choice. But this outcome is rare. Across thousands of tracked campaigns, our average response rate is 1.89% with a range of 0.98% to 4.39%.

The Scale-Up Path

Once you've validated with 50-100 cards, here's how to scale:

Month 1: The Test 50-100 cards. $67-$135. One neighborhood. Validate the channel.

Month 2: The Expansion 200-300 cards. $270-$405. Same neighborhood + one adjacent neighborhood. Start building saturation.

Month 3: The System 300 cards/month to your core neighborhood. Add quarterly cards to past customers. $405/month + $81/quarter for follow-ups.

Month 6: The Machine 500-1,000 cards/month across 2-3 neighborhoods. Past customer follow-up on autopilot. Direct mail is now your primary lead source.

At 300 cards/month, $405/month, 1.89% response = ~6 leads/month. At $700 average job and 40% close rate, that's $1,680/month in revenue from $405 in marketing.

That's a 4x return that compounds as past customers re-book and refer.

Why $67 and Not $5,000?

Most marketing channels require a big commitment before you get data:

Google Ads: Need $1,000-$3,000/month to get enough clicks to optimize
SEO: Need 6-12 months and $2,000-$5,000/month before seeing results
Door-to-door: Need to hire a rep at $4,000-$6,000/month
Vehicle wrap: $2,500-$5,000 upfront

Direct mail lets you test with $67. If it works, scale. If it doesn't, you're out the cost of a nice dinner.

No other marketing channel gives you actionable data for this little money.

What Makes This Test Different From "Regular" Direct Mail?

Two things:

1. Handwritten, not printed. A $0.50 printed postcard at 0.40% response rate means you need 250 cards to expect one response. That's $125 for a test. And the one response is a weaker lead.

A $1.35 handwritten postcard at 2.16% response means 50 cards can generate a response. That's $67 for a test. And the response is a warmer lead.

The handwritten format makes smaller tests viable because the response rate is 5.4x higher.

2. Per-piece tracking. You know when each card was delivered. You know if it was scanned. You know your exact cost per response. No guessing.

Do This Today

Pull 50 addresses near your last job. Write a 4-sentence introduction. Upload to Mailbots. Total time: 30 minutes. Total cost: $67.

If one homeowner calls and books a $700 job, you just found a marketing channel that returns 10x and scales to as many neighborhoods as you can serve.

If nobody calls? You're out $67 and you have data. That's cheaper than one Google Ads click in some markets.

Start your $67 plumbing test at mailbots.ai. Upload 50 addresses, write your message, we handle the rest. Handwritten in real pen and ink with per-piece tracking. No platform fees, no contracts.