SERVICES · RELAY MODULES
Ecommerce margin monitoring by SKU, with floors you set and rules you approve
Margin Guard tracks what each SKU keeps after every fee, ad cost, shipping charge and landed cost, on every channel, and tells you the day one drops below the floor you set.
Margin floor alerts
SKU-3107 below its 18% floor · price change needs approval
Ecommerce margin monitoring checks what each SKU keeps after every fee, ad cost, shipping charge and landed cost, and tells you when it falls below a floor. Margin Guard (RELAY-02) does this every day for Amazon, Walmart and Shopify, drafts a pricing or ad rule for your approval and is built in your own accounts. It is an advanced Relay Module, $1,500 to $3,500 fixed in writing, and it is included in Ops Desk Growth and Scale.
How margin leaks without anyone noticing
Margin rarely falls off a cliff. It leaks a few cents at a time: a fee update in January, a surcharge in April, a peak fee in October, a repricer that chased a competitor down, a discount code that stacked with a sale. Each change is small. Together they can turn a SKU that kept $6 a unit into one that keeps 40 cents (illustrative), while the sales report still looks healthy.
That is the "revenue up, margin down" pattern. Margin Guard is built to catch it the day it starts, SKU by SKU.
What ecommerce margin monitoring watches on every SKU
Margin Guard keeps one cost line per SKU, per channel:
- Price, after promotions and coupons
- Referral or marketplace fee
- Fulfillment fee: FBA, WFS or your 3PL's pick and pack
- Storage and aged-stock charges
- Payment processing on Shopify (the published 2.9% + 30 cents on Basic is for standard cards; some cards cost more)
- Returns cost
- Ad cost per unit sold
- Shipping you pay
- Landed cost from Landed Cost Desk or your cost file
What is left is contribution margin. The full per-unit formula, with a worked example, is on our profit and cash reporting page.
Setting your floor
We do not choose your floor. We show you what each SKU keeps today, and you decide where the line goes. You can mix floor types by SKU group.
| Floor type | How it works | When it fits |
|---|---|---|
| Contribution margin percent | Alert when a SKU keeps less than, say, 25% of price after every cost | Most SKUs |
| Dollars per unit | Alert when a SKU keeps less than, say, $4.00 a unit | Low-price SKUs, where a percent hides a thin dollar amount |
| Ad cost cap per unit | Alert when ad cost per unit sold passes, say, $3.00 | SKUs where ad spend swings margin week to week |
Illustrative · sample figures. You set the real floors in the spec.
A $12.99 accessory at 25% keeps $3.25 (illustrative), which may not cover a single return. That is why low-price SKUs usually get a dollar floor alongside the percent.
What triggers an alert
Alerts run after each daily data refresh and whenever a cost input changes. Each one names the SKU, the channel, margin now against the floor, the cause and one suggested action.
- A fee change on a channel.
Three 2026 examples on Amazon alone: FBA fulfillment fees rose an average $0.08 a unit on Jan 15, 2026 (Amazon's fee announcement); a 3.5% fuel and logistics surcharge on US FBA fulfillment fees took effect Apr 17, 2026, about $0.17 a unit, which Amazon described as temporary (Digital Commerce 360, Apr 3, 2026); and the holiday peak fee, about $0.32 a unit on average, runs from Oct 15, 2026 to Jan 14, 2027 (AMZ Prep, reporting Amazon's announcement). Current FBA rates are tracked on our Amazon FBA fees in 2026 guide.
- A price change
from a repricer, a promotion or a discount code.
- Orders sold below the floor.
An order-level check catches the stacked coupon that the SKU average hides.
- A new landed cost
from your supplier, freight forwarder or broker.
- Ad cost per unit above your cap
for a run of days you set.
- A SKU with no cost on file.
It is flagged and listed, never treated as free.
After an alert: who decides what
Margin Guard drafts the fix, a person checks it and you approve it, with every step logged.
| Step | Automated | Person |
|---|---|---|
| Alert raised | Yes, after each daily refresh | |
| Cause checked | Your ops lead on Ops Desk, or your team on a module-only build | |
| Suggested action | Drafted: raise price inside your band, cap or pause an ad, bundle, renegotiate cost | Reviewed before it reaches you |
| Approval | You, in writing, by email or ticket | |
| Rule applied and logged | Yes, with who approved and when |
Margin Guard never sets a price below your floor and never moves a price outside the band you approved. The band also respects each channel's own price controls. Walmart's Repricer only accepts an item into a strategy when it has both a minimum and a maximum price (Walmart Marketplace Learn, May 26, 2026), so your floor becomes the Repricer minimum. Walmart's Pricing Rule also unpublishes offers priced egregiously higher than comparable prices (Dec 12, 2025), so the ceiling of your band matters as much as the floor. Our guide to a Walmart item unpublished covers what to do if it happens.
What it connects to
Margin Guard reads cost and price data from each channel through official interfaces, under named-user access.
- Amazon:
settlement reports and the SP-API Finances API for the fees actually charged; the Product Fees API for the fee estimate at a new price; FEE_PROMOTION and ANY_OFFER_CHANGED notifications for fee promotions and Buy Box or price moves.
- Walmart:
payment reports for fees charged; item prices and Repricer strategy settings through the Pricing APIs; Buy Box and offer-unpublished event notifications.
- Shopify:
orders, discounts, payment fees and refunds.
- Ad consoles:
spend by campaign, read-only, mapped to SKUs.
- Your repricer,
if you use one: its floor and ceiling settings, checked against your approved band.
- Landed cost table
from Landed Cost Desk or your own file.
Margin Guard feeds the margin panel in Profit and Cash Pulse, so the daily dashboard and the alerts never disagree.
How the build runs and how you accept it
Week 1 is the spec: floors by SKU group, triggers, the price band per SKU and the approval route. Weeks 1 to 2 connect the data. Weeks 2 to 3 build the margin table, the alerts and the approval log. Acceptance runs in weeks 3 to 4, and the second half of the fee is due only when every test passes.
The acceptance tests in a typical Margin Guard spec:
- Every active SKU has a margin line on every channel it sells on.
- A test fee change raises an alert on each affected SKU within one daily refresh.
- A test rule cannot push a price below the floor or outside the band.
- Every SKU without a cost is listed.
- Each alert links to its source report line.
- The approval log records who approved what, and when.
Price, timing and what you own
Margin Guard is an advanced module: $1,500 to $3,500, fixed in writing before the build, built in 1 to 4 weeks. You pay 50% at the start and 50% at acceptance, and anything that fails acceptance is fixed free for 60 days. It is included in Ops Desk Growth ($2,499 a month) and Scale (from $4,499 a month). Module Care is included on any monthly plan, or 10% of the build cost a year otherwise. See all terms on pricing.
Founding offer: 20% off the module build, plus 20% off monthly plans for the first 6 months, for our first 25 clients or until Jan 31, 2027, whichever comes first.
Floors, rules, alerts and the approval log stay in your accounts. Named user access with multi-factor authentication. Never your owner password. No bank, payout or legal-entity permissions.
Who it is for
Margin Guard suits brands whose fees, ad costs or product costs move margin from week to week, usually on two or more channels. It is not a repricer license and not ad management. Ad management is a separate flat add-on: $299 a month up to $5,000 in spend, $599 a month up to $20,000. If you sell only on Shopify and only need order-level margin alerts, a low-cost app may be enough. For the wider pattern, read revenue up, margin down, and see all ten modules on the Relay Modules hub.
How much does Margin Guard cost?
It costs $1,500 to $3,500 to build, fixed in writing before we start. The price depends on how many channels, SKUs and cost sources it covers. It is included in Ops Desk Growth at $2,499 a month and Scale from $4,499 a month, where your ops lead also works the alerts every business day.
Will it change our prices on its own?
Only inside the price band you approve in writing, and never below your floor. Anything outside the band waits for you. Every change, automatic or approved, is logged with the rule, the time and who approved it, so you can see exactly what moved and why.
Do we need a repricer?
No. If you use one, Margin Guard checks that its floor and ceiling match your approved band, and on Walmart your floor becomes the Repricer minimum. If you do not, Margin Guard drafts price changes for you to approve and apply.
How often does it check margin?
After each daily data refresh, and again whenever a fee, a price or a landed cost changes. Fee changes from Amazon, Walmart and Shopify are re-run against every affected SKU, so a surcharge shows up as a list of SKUs below floor rather than as a slow drift you find at month end.
Does it manage our ads?
No. It flags SKUs where ad cost per unit passes your cap and suggests a cap or pause for you to approve. Running campaigns is a separate flat add-on: $299 a month up to $5,000 in spend, or $599 a month up to $20,000, never a percentage of ad spend. If an agency runs your ads, Margin Guard gives them the same per-SKU numbers.
What if our product costs are rough estimates?
We start with your current estimate, label it as an estimate on every screen and replace it when real invoices arrive. SKUs with no cost at all are listed, never treated as free. Landed Cost Desk can build the real per-unit cost from your invoices.
A free Profit Leak Scan shows margin by SKU and channel after every fee, so you can see which floors you would need before you build anything.
Ecomrelays LLC is a Texas company. Part of our team works outside the US, as one managed team with a named US-facing lead. 597 Mountcastle Dr, Rockwall, TX 75087. +1 (469) 331-3129.
Sources9 sources
- 01sellersasksellers.comAmazon's announcement text: FBA fees up an average $0.08 a unit from Jan 15, 2026; checked Oct 20, 2026Primary
- 02digitalcommerce360.com3.5% fuel and logistics surcharge on US FBA fees from Apr 17, 2026, about $0.17 a unit; MCF from May 2, 2026; checked Oct 20, 2026Primary
- 03amzprep.com2026 holiday peak fee Oct 15, 2026 to Jan 14, 2027, about $0.32 a unit, as reported from Amazon's announcement; checked Oct 20, 2026Primary
- 04marketplacelearn.walmart.comitems need a minimum and maximum price to join a Repricer strategy, updated May 26, 2026; checked Oct 20, 2026Primary
- 05marketplacelearn.walmart.comWalmart Pricing Rule unpublishes offers priced egregiously higher than comparable prices, updated Dec 12, 2025; checked Oct 20, 2026Primary
- 06shopify.comShopify Basic online card rate 2.9% + 30 cents on standard cards; checked Oct 20, 2026Primary
- 07developer-docs.amazon.comFEE_PROMOTION and ANY_OFFER_CHANGED notifications; checked Oct 20, 2026Primary
- 08developer-docs.amazon.comFinances API v2024-06-19, Product Fees API; checked Oct 20, 2026Primary
- 09developer.walmart.comWalmart Buy Box and offer unpublished events; Pricing and Repricer strategy APIs; checked Oct 20, 2026Primary
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