ArbitragePro+ blog — source, compare, resell

Practical methods, comparisons and guides for online arbitrage.

Profitability · 8 min read

FBA Storage: Factoring Time and Surcharges into the Calculation

Project FBA storage by cohort and duration, with dated volumes, rate cards, and surcharges, without turning a turnover assumption into a certain cost.

Profitability · 8 min read

FBA Fees: Checking Weight, Dimensions, and Size Tier

Check the packed product measurements, the FBA size tier, and the dated rate card before estimating fees, then treat discrepancies as alerts.

Profitability · 8 min read

Amazon Commission: Why the Rate Depends on the Category

Check the category, base, and applicable Amazon rate card before calculating a commission, then reconcile the estimate with invoiced fees.

Profitability · 8 min read

Calculating the Breakeven Resale Price

Calculate a breakeven Amazon resale price with fixed costs, variable costs, and assumptions kept separate from confirmed amounts before any purchase decision.

Profitability · 8 min read

ROI or Net Margin: Which Filter Should You Use in Amazon Arbitrage?

Compare ROI and net margin to filter an Amazon opportunity without mixing capital employed, net revenue, and estimated profit before purchase.

Profitability · 8 min read

Calculating the Full Landed Cost Before Amazon

Calculate a traceable Amazon FBA landed cost, from supplier cost to selling fees, with assumptions kept separate from confirmed amounts.

Profitability · 8 min read

Allocating Supplier Shipping Costs Per Product

A reproducible method for allocating a supplier order's shipping costs across products without distorting the landed cost or the estimated margin.

Profitability · 8 min read

Normalizing Currencies Without Hiding the Cost of Exchange

Normalize supplier prices into a common currency without confusing the reference rate, the transaction rate, fees, and the conversion date.

Compliance · 8 min read

Product Feed: Checking Usage Rights Before Connecting

Check the license, terms of service, purposes, frequency, and redistribution rights before connecting a product feed, with an evidence and decision matrix.

Sources · 8 min read

Testing a New Supplier with a Canary Batch

Test a supplier catalog on a reversible canary batch: entry criteria, evidence, controls, stop conditions, and a decision before scaling up.

Sources · 8 min read

Building a Reliability Score for a Supplier Catalog

Build a supplier reliability score based on timestamps, errors, and data checks, with an explicit, revisable weighting scheme.

Matching · 8 min read

Matching a Product by Image and Name When the EAN Is Missing

Combine image, brand, model, variant, and name to propose a match without an EAN, with explicit thresholds and mandatory human validation.

Data quality · 8 min read

One GTIN Across Multiple Variants: Detecting Dangerous Duplicates

Spot repeated GTINs, distinguish legitimate offers from contradictory variants, and organize a reliable review backed by GS1 evidence.

Profitability · 8 min read

Tiered Discounts: Calculating the True Unit Price

Calculate the unit price at each tier by factoring in packaging, MOQ, orderable quantity, taxes, and fees without confusing a displayed discount with actual cost.

Data quality · 8 min read

Boolean Stock vs. Exact Quantity: What the Data Actually Proves

Distinguish boolean availability, exact quantity, thresholds, and supplier lead times so a stock signal is never mistaken for false certainty.

Data quality · 8 min read

Price and Stock Freshness: Defining a Trust Window

Define a separate freshness policy for prices and stock, based on timestamps, observed cadence, errors, and order risk.

Data quality · 8 min read

CSV, XML, API, or FTP: Choosing the Right Supplier Feed

Compare CSV, XML, HTTP APIs, and FTP drops by structure, frequency, resumability, security, and traceability to choose a durable supplier feed.

Data quality · 8 min read

Comparing Two Suppliers on the Same EAN Without Getting It Wrong

Compare two offers sharing the same EAN by checking variant, unit price, taxes, stock, packaging, and landed cost before making a reliable decision.

Data quality · 8 min read

How to Validate a GTIN Check Digit Without False Positives

Calculate a GTIN's check digit, preserve leading zeros, and distinguish mathematical validity, GS1 attribution, and the right product with a clear method.

Data quality · 8 min read

Wholesale Catalog: Columns to Check Before Import

A practical method for checking identifiers, prices, stock, currency, lot sizes, and images in a wholesale catalog before any reliable data import.

Comparison · 7 min read

SellerAmp Alternatives in 2026: A Comparison

A comparison of SellerAmp alternatives for product analysis and arbitrage sourcing: criteria and strengths to weigh up.

Comparison · 7 min read

Keepa Alternative in 2026: A Comparison

A comparison of Keepa alternatives for tracking Amazon prices and finding profitable gaps: criteria and strengths to weigh up.

Comparison · 9 min read

Keepa, SellerAmp, Actorio: A Tool Comparison for Amazon Arbitrage

Keepa, SellerAmp or Actorio: what each tool actually does, who it's for, and how they complement a multi-source comparison tool.

Seller guide · 11 min read

Selling on Amazon in 2026: Seller Account, VAT/OSS, FBA or FBM

A practical guide to selling on Amazon: opening a seller account, understanding VAT/OSS, and choosing between FBA and FBM.

Suppliers · 5 min read

BigBuy: A Review of This Dropshipping Wholesaler and How to Use It for Arbitrage in 2026

BigBuy in 2026: a dropshipping and wholesale platform with 24 stated categories, its strengths, its limitations, and its integration status in ArbitragePro+.

Suppliers · 5 min read

Eany.io: A Review of This B2B Marketplace and How to Use It for Arbitrage in 2026

Eany.io in 2026: an AI-assisted B2B marketplace, a network of verified EU suppliers, and its active integration in ArbitragePro+'s sourcing catalog.

Suppliers · 5 min read

Qogita: Review, Catalog, and How to Use It for E-Commerce Arbitrage in 2026

Qogita in 2026: beauty/health/hygiene catalog, verified suppliers, and how its prices are continuously compared to resale prices in ArbitragePro+.

Product guide · 5 min read

Profit+: ArbitragePro+'s upcoming Amazon profitability dashboard

Profit+ is ArbitragePro+'s Amazon profitability-tracking module currently in development: real COGS calculation, French tax rules, and automatic feedback into sourcing when a margin degrades.

Product guide · 5 min read

Analyzer+: the Amazon product analysis tool with real net margin calculation

Analyzer+ cross-references a product's Keepa price history with ArbitragePro+'s supplier catalog and calculates the real net margin under French tax rules before you decide to buy.

Product guide · 6 min read

ArbitragePro+: the multi-source sourcing engine for online arbitrage

How ArbitragePro+ continuously compares over 6 million product references across 4,600 sources to surface profitable price gaps, from EAN/ASIN matching to the final opportunity.

Marketplaces · 8 min read

Amazon, Cdiscount, Bol.com: Which Marketplace Should You Choose for Arbitrage?

A comparison of European marketplaces for arbitrage: Amazon, Cdiscount, Bol.com — audience, competition and how to choose.

Amazon · 9 min read

Amazon Arbitrage Explained Step by Step

How Amazon arbitrage works in 2026: the Buy Box, ungating, FBA/FBM, restrictions, and a method to get started without costly mistakes.

Comparison · 7 min read

Actorio Alternatives in 2026: A Comparison

A comparison of Actorio alternatives for arbitrage and multi-source sourcing: criteria and strengths to weigh up.

Calculation & margins · 7 min read

Calculating Your Net Margin in Arbitrage (Method + Example)

How to calculate your net margin in Amazon/eBay arbitrage: fees, VAT, customs and a worked example.

Sources · 9 min read

The Best B2B Wholesalers for Arbitrage in Europe (and Beyond)

An overview of B2B wholesalers for arbitrage: Qogita, Faire, Ankorstore, BigBuy… with their strengths by category.

Sourcing · 8 min read

How to Find Profitable Products to Resell

A repeatable method for finding profitable products to resell: criteria, sources, and signals to check before buying.

Fundamentals · 6 min read

Online Arbitrage vs. Retail Arbitrage: What's the Difference?

Online arbitrage compared to retail arbitrage: pros, cons, and which one to start with.

Pillar guide · 12 min read

The Complete Guide to Online Arbitrage in 2026

Everything you need to know about online arbitrage in 2026: the principle, profitability, sourcing, margin calculation and the right tools.