Knowing your cost per job

1The four numbers you actually need

No spreadsheet required. Four figures — you probably know three already.

• Average job value. The typical booked job for the service you're advertising. Not your biggest job ever — the normal one.
• Profit margin on that job. After materials, labour (including your own time at a fair rate), travel, and subcontractors. Revenue isn't profit.
• Close rate. Of every ten people who enquire, how many actually book? Seven out of ten = 70% close rate.
• Click-to-enquiry rate. Of every hundred people who click your ad, how many contact you? Estimate to start; refine over time.

2Working backwards from profit

This is the useful bit. Start from profit per job, work back to the max you can spend per click.

Here's a clearly hypothetical teaching example — not a real-world benchmark:

• Typical job revenue: $800
• Profit after all costs: $300 ← your ceiling
• You're willing to spend up to $100 to win one job (keeping $200)
• Close rate: 70% → it takes ~1.4 enquiries to land one booking
• Max cost per enquiry: $70 ($100 ÷ 1.43)
• Click-to-enquiry rate: 5% → it takes ~20 clicks to get one enquiry
• Max cost per click: $3.50 ($70 ÷ 20)

Your actual numbers will shift. But doing this once — even roughly — tells you whether current click prices make sense, or whether you need to improve your close rate first.

4Why this unlocks newer low-cost channels

Once you know your max cost per enquiry, you can evaluate channels quickly — before spending a dollar.

• Google remarketing now starts at 100 active users — a threshold Google lowered in December 2024. If your site gets 150+ visitors a month, you can advertise to people who've already looked. Warm traffic tends to cost less per click and close higher.
• Google Local Services Ads charge per lead, not per click. If your numbers say you can afford $60 per enquiry and the platform charges $40, the decision is straightforward. (Per-lead pricing varies by trade and market — check current rates in your area.)

Knowing your ceiling number turns channel evaluation from a guess into arithmetic.

5How to track this without any special tools

You don't need software. You need a habit.

1. Ask every new customer how they found you. At the start of the job or when they call: "Can I ask how you found us?" Keep a tally — Google ad, referral, Facebook, saw the van.
2. Note whether each enquiry became a booking. One column for contacts, one for bookings. After a month, you have your close rate.
3. Check your ad platform weekly. Google Ads and Meta both show clicks and costs. Divide total spend by form submissions or phone calls in the same period — that's cost per lead from that channel.
4. Every few weeks, calculate cost per booked job. Take those leads, count how many became bookings, divide spend by bookings.

The businesses that know their numbers aren't running fancy systems. They're writing things down.

6Common mistakes

• Using revenue instead of profit. A $500 job where you keep $80 is completely different from one where you keep $300. Work from what you actually keep.
• Not tracking by source. "Leads came in" isn't useful. You need to know where — so you can compare channels. A referral that costs nothing closes differently from a cold ad click.
• Stopping at cost per lead. Cost per lead is a stepping stone. Cost per booked job is the number that tells you whether you're making money on your marketing.
• Giving up too early. A week of data means nothing. You need at least a month — ideally three — before averages are reliable enough to act on.
• Forgetting your own time. If a $600 job takes six hours including drive time, your labour cost isn't zero because you're the owner. Price your time in, or your profit figures are fiction.