Build the acquisition model all the way through the return

A useful acquisition scenario follows an order beyond checkout, including refunds, fulfilment and payment costs, so the advertising budget rests on retained contribution rather than initial sales.

An acquisition plan can look profitable because it ends too early. The model records a purchase, subtracts product cost and advertising, and assumes the remaining amount is available to the business.

Real orders can be returned, cancelled, replaced or expensive to support. Some costs remain even when the revenue disappears. A CMO’s scenario should carry the order through that journey before setting an acquisition ceiling.

The following example is deliberately simple and entirely hypothetical. Its purpose is to make the treatment of costs explicit enough for finance to replace every assumption with the company’s own data.

Define one cohort and one period

Take 100 initial orders at €100 each, excluding tax. Initial revenue is €10,000. Assume the model follows this cohort through a sufficiently long returns window and that every returned order receives a full product-price refund.

Suppose 20 orders are returned. Retained revenue is therefore €8,000. For simplicity, assume returned products are fully recoverable into inventory without damage or markdown; a real business must model any loss.

Use the same cohort throughout. Mixing this month’s acquisition spend with this month’s returns from older orders can obscure the economics of the customers actually acquired.

Distinguish estimates from settled outcomes. Early cohort reports can be useful, but they should show which return and repeat-purchase assumptions remain unresolved.

Follow the costs that do not disappear

Assume product cost is €40 for each retained order: 80 multiplied by €40 gives €3,200. Outbound fulfilment costs €8 on all 100 shipped orders, or €800.

Return processing costs €10 for each of the 20 returns, adding €200. Assume payment costs of €3 on every original order are not recovered, adding €300.

The cohort therefore leaves €8,000 minus €3,200, €800, €200 and €300: €3,500 before advertising. With €2,500 advertising spend, it leaves €1,000 contribution after advertising and before fixed overhead.

The assumptions are intentionally visible. If shipping is charged to customers, refunds are partial, returned stock loses value or processing fees differ, the calculation must change accordingly.

Calculate the ceiling and the operating target separately

Under these assumptions, €3,500 is the advertising break-even ceiling for the cohort before fixed overhead. Dividing by 100 initial orders gives €35 per initial order.

That is not a recommended acquisition target. The company may need contribution toward overhead, cash reserves and profit, so the operating target should sit below the ceiling by an amount management deliberately chooses.

Also define the acquisition unit. Cost per order is not cost per new customer when some buyers place multiple orders or were already customers. Relabel the model or adjust the denominator rather than using the terms interchangeably.

This distinction becomes important when comparing campaigns that attract different mixes of new and returning customers.

Stress the assumption that can overturn the case

Now raise the hypothetical return rate to 30%, keeping the other unit assumptions unchanged. Retained revenue becomes €7,000 and product cost for retained orders becomes €2,800.

Outbound fulfilment remains €800, return processing becomes €300, and payment costs remain €300. Contribution before advertising is €2,800; after the same €2,500 advertising spend, only €300 remains.

A ten-percentage-point return-rate change reduced contribution after advertising by €700. The original checkout revenue could look identical while the eventual economic result differs substantially.

Run similarly grounded sensitivities for discounts, fulfilment cost and product mix. Record the source and owner of each assumption. Avoid combining every optimistic assumption into the base case simply to make the target acquisition cost fit.

Check what your systems actually report

Google Ads guidance on conversion values makes the supplied value central to value-based reporting. If the account receives initial revenue, it should not be interpreted as retained contribution without the necessary adjustments.

Shopify’s profit-report guidance likewise depends on recorded cost information. A platform’s profit label does not remove the need to understand which costs are included.

Use a small reconciliation sample to compare the model with actual orders, refunds and fees. Resolve definition differences before scaling the calculation across the whole acquisition budget.

Add future value cautiously

Repeat purchasing may justify an initial acquisition cost that exceeds first-order contribution. Model that as a separate, dated cohort forecast with retention, margin and service assumptions.

Do not let speculative lifetime value hide a weak first-order model. Show the amount and timing of later contribution required to recover the initial shortfall, and what happens if it arrives more slowly.

Include a cash view where the business pays advertising and fulfilment before collecting or retaining customer revenue. Economic payback and cash availability are related but distinct constraints.

The finished scenario should make disagreement productive. Marketing can challenge the demand assumptions, operations can challenge delivery costs, and finance can challenge the contribution definition. The acquisition budget becomes stronger because everyone can see where its room for error actually lies.