Tactical Arbitrage and Repricing: Using Both in Your OA Workflow
Most online arbitrage sellers understand what Tactical Arbitrage does: it scans thousands of retail websites, compares prices to Amazon, and flags products where the spread is large enough to be profitable after fees. Fewer sellers think carefully about what happens next.
TA's job ends at the purchase decision. The moment your inventory arrives at an FBA fulfilment centre, a different problem begins, and it is one that Tactical Arbitrage was not built to solve.
This guide covers how the two tools fit together, how to translate your TA profit data into a repricing floor, and the single sourcing mistake that erodes OA margins even when the initial spread looks solid.
TL;DR: Tactical Arbitrage identifies products where the sourcing spread is profitable. A repricer manages your price once inventory is live on Amazon, protecting your margin floor and keeping you competitive for the Buy Box. The two tools serve different stages of the same workflow. TA finds the opportunity. A repricer protects the margin once inventory is live. Set your repricing minimum price using your actual landed cost from TA, not the projected profit estimate alone. View integrations.
What Tactical Arbitrage does and where it stops
Tactical Arbitrage solves one problem: finding products where the spread between a retail source price and the current Amazon selling price is large enough to be profitable after fees. It does not manage what happens to your price once the product is live on Amazon.
TA scans online retailers, pulls product data, cross-references it against Amazon, and applies a fee model to estimate net profit and return on investment. For each scan result you see the source price, the Amazon selling price, the estimated FBA fee, the referral fee percentage, the number of competing sellers, and a projected profit and ROI figure. Keepa price history data is built in, so you assess whether the current Amazon price is typical or anomalous.
This is sourcing intelligence. It helps you decide which products are worth buying and at what quantity. It tells you what your profit looks like at the price Amazon is selling for today.
What TA does not do:
It does not monitor your listings after you go live. It does not know when a competitor drops their price by 15% and pushes you off the Buy Box. It does not enforce a minimum price below which you will not sell. It does not respond to pricing events on Amazon in real time.
The gap between "profitable at the time of sourcing" and "profitable at the time of sale" is where OA margins are made or lost. That gap is filled by a repricer, not by Tactical Arbitrage.
Why sourcing intelligence alone is not enough once inventory goes live
The Amazon listing you sourced into is not the listing your inventory lands in. Competitor prices, seller count, and Buy Box eligibility shift during the two to four weeks between purchase and FBA arrival.
When you source an OA product, you are looking at a snapshot: the Amazon price today, the competition today, the Buy Box price today. Your decision is based on that snapshot being representative of what the product sells for once your inventory is live.
It often is not.
FBA shipments take time. During that window, other sellers on the listing reprice. New sellers enter the listing. Sellers who were out of stock restock. The price that justified your sourcing decision four weeks ago is not necessarily the price available when your units check in.
Without a repricer, you set your price manually at launch and leave it there. Three scenarios follow:
Scenario 1: Your price is above the competitive FBA offers on the listing. You do not win the Buy Box. Your units sit at FBA, accruing storage fees, while competitors sell at prices below yours.
Scenario 2: Your price is competitive at launch but a competitor drops their price a week later. Without repricing, you stay at your original price and lose the Buy Box. Same result as scenario 1.
Scenario 3: You manually reprice when you notice the problem. By the time you adjust, you have already missed sale velocity. If you reprice without a floor, you risk dropping below your minimum viable margin.
All three scenarios are solved by a repricer with a Profit Protection floor. Repricer.com monitors competitor offers and responds in under 90 seconds. The floor is calculated from your actual cost inputs and is enforced on every pricing event. Your price stays competitive without ever dropping below the point where the sale stops being profitable.
The OA workflow: TA finds the opportunity, a repricer protects the margin
Online arbitrage has two distinct phases that require different tools. TA covers the sourcing phase. A repricer covers the live-pricing phase. Neither tool substitutes for the other.
The complete OA workflow looks like this:
Phase 1: Source (Tactical Arbitrage)
Scan retail sources for products with a profitable spread. Filter by your minimum ROI, maximum BSR, and maximum seller count. Check Keepa data to confirm the current price is representative of the 90-day range. Identify your buy quantity based on velocity data and capital allocation. Purchase the inventory.
Phase 2: Prep and ship
Apply your prep and labelling costs. Ship to FBA. This is where your landed cost becomes fixed: source price plus prep plus inbound shipping.
Phase 3: Go live (Repricer)
Your units check in at FBA. Your repricer begins monitoring the listing from the moment you are live. It competes for the Buy Box against other FBA offers, adjusting your price within the bounds of your minimum floor and maximum ceiling. The floor is derived from your landed cost. The repricer does not know your TA profit projection. It knows your minimum price, and it enforces it on every price change it makes.
Phase 4: Sell
Your repricer wins the Buy Box at the highest price the competitive environment supports, subject to your floor. Sales happen without manual price intervention.
The minimum viable OA tool stack for a 3P seller running FBA arbitrage:
Tactical Arbitrage for sourcing (scans, profit filtering, Keepa integration)
A repricer with profit floor enforcement for live pricing
Seller Central for inventory management and fee confirmation
Some sellers add a Keepa standalone subscription for deeper price history analysis and a profit and loss tracker for accounting purposes. Those are useful but not prerequisites. The critical gap in most OA setups is the repricer, not additional sourcing data.
How to connect your sourcing cost from Tactical Arbitrage to your repricing floor
The data Tactical Arbitrage gives you for each sourced product maps directly to the inputs your repricing floor requires. The connection is explicit, not approximate.
Tactical Arbitrage calculates projected profit using four inputs: your buy cost, the estimated FBA fulfilment fee, the referral fee percentage, and the current Amazon selling price. It outputs an estimated net profit figure and an ROI percentage.
When you set your Profit Protection floor in Repricer.com, you need the same four inputs expressed differently:
One important distinction: TA uses ROI (profit divided by cost) in its default output. Profit Protection works with margin (profit divided by revenue). These are not the same figure and should not be swapped.
To convert: if TA shows a 25% ROI on a product costing $10.00, your profit is $2.50. The sell price needed to achieve that profit is $12.50. The margin on a $12.50 sale with $2.50 profit is 20%. For a 25% ROI target, the equivalent margin target is 20%.
A practical rule: your landed cost is the only TA figure that always requires adjustment before it goes into Profit Protection. TA's buy cost does not include your prep fee or your inbound shipping cost. Those are paid after TA flags the opportunity and before your inventory checks in. Always add them to get your true landed cost.
For the FBA fee, TA provides an estimate. Seller Central confirms the actual fee once an ASIN is processed. For repricing floor purposes, use the actual confirmed fee rather than the TA estimate wherever they differ. The difference is small on standard-size products and material on oversize or apparel items where TA's estimate relies on approximate dimensions.
The Repricer.com net margin repricing guide covers the full floor calculation methodology, including how referral fee percentages vary by category and how to account for storage costs in the minimum price formula.
Setting minimum prices based on TA profit calculations
Your repricing floor is the price below which the sale destroys margin. It is calculated from your landed cost, not from the TA profit estimate at the time of sourcing.
Here is how the floor calculation works using a real OA example:
Sourcing data from TA scan:
Source price: $8.00
Current Amazon selling price: $22.00
Estimated FBA fee (TA): $3.40
Referral fee: 15%
TA projected ROI: 87.5%
That ROI looks excellent. Before you set your repricing floor on that figure, adjust for your actual costs:
Adjusted costs:
Source price: $8.00
Prep fee: $0.75 per unit
Inbound shipping to FBA: $0.45 per unit
Landed cost: $9.20
FBA fee (confirmed in Seller Central): $3.55
Storage cost per unit (estimated 60-day hold): $0.35
Applying the Profit Protection formula:
Minimum price = (landed cost + FBA fee + storage cost) / (1 - referral fee % - target margin %)
Using a 20% target margin:
Minimum price = ($9.20 + $3.55 + $0.35) / (1 - 0.15 - 0.20) = $13.10 / 0.65 = $20.15
At the current Amazon price of $22.00, you have $1.85 of headroom before you hit your floor. That is enough to compete with other FBA sellers in the $20.15 to $22.00 range without destroying your margin.
If competitors drop to $19.99, your repricer holds at $20.15. You lose the Buy Box on that listing, but you do not sell below your margin threshold. TA showed you an 87.5% ROI at $22.00. Without a floor, a price war on this listing destroys it. With a floor, the minimum viable outcome is protected on every sale.
Notice what changed between the TA scan figure and the actual floor: TA's buy cost was $8.00. Your landed cost after prep and shipping was $9.20. The difference moved your floor by roughly $1.80 (accounting for the fee structure). TA's estimate was directionally correct but not suitable for direct use as a repricing input.
How to avoid the most common mistake: sourcing without a repricing strategy
The most common OA margin problem is not bad sourcing. It is sourcing without a mechanism to protect the margin once inventory is live. Two failure modes follow, and both are preventable.
Failure mode 1: No repricer, manual pricing
The seller sources well using TA. They list at a competitive price at launch. They do not check their Buy Box share for two weeks. During that time, competitors repriced. The seller's price is now above the Buy Box price. Units sit at FBA. Storage fees accumulate. Eventually the seller drops their price manually, but by then the demand window has passed or the competition has thinned and they reprice below what the listing warranted.
The sourcing was correct. The live pricing was unmanaged.
Failure mode 2: Repricer with no floor
The seller sets up a repricer but does not configure a minimum price. The repricer competes aggressively for the Buy Box and drops the price as competitors drop. The product eventually sells, but at a price that does not cover landed cost, FBA fees, and referral fees. The sale generates a loss.
The repricing tool was present. The floor was absent.
Both failure modes are solved by the same configuration: a repricer with Profit Protection enabled and a floor calculated from your actual landed cost. For OA sellers running Tactical Arbitrage, that floor is derived from TA's fee data corrected for your actual prep and shipping costs.
The repricing strategy does not need to be complex. For an OA seller running standard FBA arbitrage:
Set your minimum price using the Profit Protection formula with your actual landed cost per ASIN
Set your maximum price at 10% to 15% above the current Buy Box price (or higher for seasonal products with limited stock)
Let the repricer handle everything between floor and ceiling
You update the floor when your cost basis changes: when prep costs change, when storage fees change, when Amazon adjusts referral fees or FBA rates. Everything else is automated.
Repricer.com integrations allow you to connect Seller Central directly, so FBA fee data from Amazon feeds into your repricing configuration without manual entry. The 14-day free trial starts in Safe Mode, where the full repricing logic runs without submitting live price changes for the first seven days.
Book a Demo to see Profit Protection set up against a real OA ASIN in Safe Mode, with the floor calculated from the landed cost methodology above.
Key Takeaways
Tactical Arbitrage solves the sourcing problem, not the live pricing problem. Its job ends at the purchase decision.
The market shifts between sourcing and sale. FBA lead times of two to four weeks mean the competitive position you sourced into is not the one your inventory lands in.
The minimum viable OA tool stack is Tactical Arbitrage for sourcing and a repricer with a profit floor for live pricing. Neither substitutes for the other.
TA's cost data feeds directly into your repricing floor, but landed cost must include prep and inbound shipping, not the source price TA records alone.
Convert TA's ROI to margin before entering it as a target in Profit Protection. They measure different things and produce different floor prices.
Two failure modes kill OA margins: no repricer (unmanaged live pricing) and a repricer with no floor (margin erosion from price wars). Both are solved by Profit Protection configuration.
Action Plan
For every OA product you source via TA, record your actual landed cost at the point of purchase: source price plus prep fee plus inbound shipping per unit. This is the number that goes into your repricing floor, not the TA buy cost alone.
Confirm FBA fees in Seller Central for each new ASIN before setting your floor. TA's estimate is a useful filter during scanning. The confirmed fee is what you use for Profit Protection.
Apply the Profit Protection formula: minimum price = (landed cost + FBA fee + storage cost per unit) / (1 - referral fee % - target margin %). Use the net margin repricing guide for the full worked methodology.
Convert your target ROI to a margin percentage for entry into Profit Protection. Divide your expected profit by the expected sale price, not by your cost.
Set your repricing ceiling at 10% to 15% above the current Buy Box price for standard OA products. Adjust upward for seasonal or clearance items where the demand window is short and stock is limited.
Enable Safe Mode for the first seven days of your Repricer.com trial. Review what the repricer would have done on your OA ASINs before any live prices change. Adjust floors and ceilings based on what you see.
Sign up for a 14-day free trial at Repricer.com and configure Profit Protection for your five highest-velocity OA ASINs in the first week. That is enough data to validate your floor methodology before rolling it out across your full catalogue.
Frequently Asked Questions
1. What is Tactical Arbitrage?
Tactical Arbitrage is an online arbitrage sourcing tool that scans thousands of online retailers and compares product prices to Amazon. For each product it finds, it estimates the FBA fee, referral fee, and projected profit based on the difference between the retail source price and the current Amazon selling price. It includes Keepa price history data to help sellers assess whether the current Amazon price is representative of the product's typical range. Tactical Arbitrage is used to decide which products are worth sourcing. It does not manage pricing once those products are live on Amazon.
2. Do I need a repricer if I use Tactical Arbitrage?
Yes. Tactical Arbitrage and a repricer solve different problems. TA helps you decide which products to buy and at what price the sourcing math works. A repricer manages your price once your inventory is live on Amazon, winning you Buy Box time against competing offers and enforcing a minimum price floor below which you will not sell. Without a repricer, your price is static after launch. Competitor prices are not. The margin TA identified at the time of sourcing will not protect itself once your units are live. A repricer with Profit Protection does.
3. How does Tactical Arbitrage fit into an online arbitrage seller's tool stack?
Tactical Arbitrage is the sourcing layer of the OA tool stack. It runs before you buy inventory. The minimum tool stack for an OA seller running FBA arbitrage is TA for sourcing and a repricer with a profit floor for live pricing. Some sellers add a dedicated P&L tracker for accounting and a Keepa subscription for deeper price history analysis beyond what TA provides natively. The most common gap in OA tool stacks is not a shortage of sourcing data, it is the absence of automated live pricing. TA finds opportunities. Without a repricer, those opportunities are not fully protected once inventory is live.
4. How do I use my Tactical Arbitrage profit data to set repricing minimum prices?
Take the buy cost TA records for the product and add your prep fee and inbound shipping cost per unit to get your landed cost. Take the FBA fee from TA as a starting estimate and confirm it in Seller Central once the ASIN is processed. Apply the Profit Protection formula: minimum price = (landed cost + FBA fee + storage cost per unit) / (1 - referral fee % - target margin %). Convert your target ROI to a margin percentage before entering it into the formula, since TA uses ROI (profit / cost) and Profit Protection uses margin (profit / revenue). For a worked example, see H2 5 of this guide above.
5. What is the minimum viable tool stack for an online arbitrage seller?
The minimum viable OA tool stack is Tactical Arbitrage for product sourcing and a repricer with profit floor enforcement for live pricing. These two tools cover the two phases where margin is made or lost: the sourcing decision and the live pricing response. Seller Central is required for inventory management and fee confirmation. Beyond that, Keepa for extended price history and a P&L tracker for accounting are useful additions. The most important upgrade for most OA sellers who are already using TA is adding a repricer with Profit Protection, not more sourcing tools.
Complete your OA tool stack with automated repricing. Try Repricer.com free for 14 days. Book a Demo to see Safe Mode running on your OA listings before any live prices change.
