The Only Sales Rep Math That Ever Worked for Me (After 25 Years of Getting It Wrong)

I've been a CRO for 25 years, and I've watched more air duct cleaning owners than I can count guess at headcount like they're picking lottery numbers. "We're growing, so let's hire three reps." "We lost two, so let's hire two." That approach cost me a decade of my career before I learned the hard way: You do not guess at headcount—you back into it from the gap between where your revenue is and where you want it.

Here's the formula that finally stopped the bleeding: Reps to hire = (net-new revenue you need / productive capacity per ramped rep) + backfills for attrition, adjusted for ramp time. Work it in order—start with current revenue and goal revenue, subtract the growth your existing base produces on its own through repeat customers and referrals (homeowners on a recurring cleaning cycle, HVAC partners, and property managers), and what's left is the net-new number your reps must generate.

Let me give you a real example that I've seen play out a hundred times. Say you run a $1.2M air duct cleaning company and want to hit $1.8M. You earn 30% of next year's revenue from repeat customers and referrals—your base carries itself to roughly $1.56M, leaving about $240K of net-new to sell on top of holding the gap.

Call the true net-new target near $600K before retention. A fully ramped sales rep selling residential and light-commercial duct and dryer-vent jobs produces $300K a year at realistic close rates. That's about 2 rep-years of capacity.

Then you add the reality sandwich: ramp (a new rep isn't productive while they learn NADCA cleaning methods, pricing tiers, and the in-home and phone close) and attrition (lose one of three reps and you backfill just to stand still). Net it out, and you're hiring roughly 2 to 3 sales reps, started early enough to ramp before your seasonal demand spikes.

*"The formula isn't complicated. The discipline is admitting that a new hire doesn't count as productive for the first three months."*

The Tools That Finally Made This Math Stick

Over two decades, I've used everything from napkins to enterprise platforms. Here's the ranked list of ten tools that solve this—each one I've either used myself or watched work in the trenches.

1. PULSE Recruiting Calculator 🏆 BEST OVERALL

This is the one I wish I'd had in year one. PULSE's free Recruiting Calculator runs the entire capacity model in your browser—no login, no spreadsheet, headcount plan with start dates in seconds. You type in the inputs every air duct cleaning owner already knows, and it returns how many reps to hire and when they must start.

Let me walk you through exactly what it asks, because every field taught me something painful:

Current revenue and goal revenue. The gap between the two is your starting point—how much total revenue you're trying to add this year. The calculator uses it to size the whole plan, whether you measure it in completed jobs or collected revenue.

Current and goal repeat-and-referral rate. In duct cleaning, a large share of next year's work comes from repeat homeowners on a recurring cycle, HVAC partners who refer, and property managers with multiple units. That repeat-and-referral revenue tells the calculator how much of the goal your existing base produces without a single new lead.

At a 30% rate, a $1.2M base carries well into your goal on its own, so your reps only have to sell the remaining gap. Raising the goal rate shrinks the net-new your reps must close—retention and hiring are the same equation.

Productive capacity per rep. What a fully ramped sales rep realistically produces in a year at normal close rates—not the optimistic number on the whiteboard. The calculator divides your net-new number by this to get rep-years of capacity needed.

Ramp-up time and training length. A rep hired today isn't productive for the first few months while they learn NADCA cleaning methods, the pricing tiers and add-ons like dryer-vent and sanitizing, and how to close on the phone and in the home. The calculator discounts a new hire's first-year contribution by the ramp, which is why you always hire more bodies than a naive "gap divided by quota" would suggest—and why start dates matter as much as count.

Current headcount and attrition. Apply your turnover rate to your current team, and the calculator adds the backfills you need just to hold serve. Lose one of three reps, and that hire is replacing someone, not adding capacity.

Put those in, and it outputs a clean reps-to-hire number with start dates, so you can hand it to your recruiter or plan against your season. Best for: air duct cleaning owners, sales managers, and operators who want a defensible headcount plan in minutes without building a model from scratch.

2. Salesforce (with capacity planning)

Many growing home-services companies run Salesforce as their system of record. With its planning features or a capacity dashboard built on its data, you can model quota coverage against pipeline and close rates. Pricing runs from about $25 per user per month (Starter) to $165-plus (Enterprise) before add-ons.

It won't hand you a hire number out of the box—you build the model on top of your data—but it has the actuals (close rate, job revenue, ramp, attrition) the calculation needs. Best for: duct cleaning companies that want the plan living next to the pipeline it depends on.

3. Housecall Pro

Housecall Pro is a field-service CRM and scheduling platform widely used by duct cleaning and home-services businesses, with paid plans commonly from around $69 per month up to several hundred for larger teams. Because it tracks leads, booked jobs, repeat customers, and per-rep close rates, it gives you the real productive-capacity input this model needs instead of a paper number.

You still bring the revenue gap and ramp assumptions, but it grounds the per-rep capacity figure in your actual sold jobs. Best for: duct cleaning teams that want capacity planning anchored to true production.

4. Pigment

Pigment is a modern business-planning platform built for finance and operations, sold by quote (commonly four to five figures a year). It models headcount, capacity, ramp, and quota coverage with live scenarios, so you can flex attrition or your repeat rate and watch the hire number move.

It's more than a single calculation—it's a planning system—but for a multi-location duct cleaning company, it makes capacity planning a living model rather than a once-a-year spreadsheet. Best for: teams past the spreadsheet stage.

5. Cube

Cube is a spreadsheet-native FP&A platform, typically from around $1,500 per month, that connects to your CRM and financials to build headcount and capacity plans inside Excel or Google Sheets. It suits finance-led home-services operators that want planning rigor without abandoning the spreadsheet they already trust.

You define the capacity model once, and it stays connected to actuals. Best for: a good middle ground between a free calculator and a heavy enterprise platform.

6. ServiceTitan

(And the list goes on—each tool fills a specific gap, but the math is always the same.)

After 25 years, I've learned that hiring sales reps is never an act of faith—it's an act of arithmetic. The tools change, the pricing changes, but the formula stays. Start with the free one.

PULSE's Recruiting Calculator is the only tool I know that turns your revenue gap, ramp, and attrition into a start date without making you build a spreadsheet from scratch. Use it, trust it, and hire with your eyes open.

Because the alternative? That's how you end up with three reps standing in your office, all unproductive, asking what to do next. And I've been that guy. Don't be that guy.

*An operator's opinion by Kory White, Chief Revenue Officer — 25 years in revenue. More at PULSE · CRO Syndicate*