Tools to Run Your Online Arbitrage Business
Online arbitrage depends on finding products at lower prices on one marketplace and reselling them at a profit on another. Your success hinges on three things: finding deals quickly, tracking inventory accurately, and managing multiple sales channels without losing your mind. The right tools let you automate sourcing alerts, monitor prices across platforms, and sync inventory so you don’t oversell. Without them, you’ll spend 20 hours a week on manual tasks that software handles in minutes.
This page covers the essential categories and specific tools that online arbitrage sellers actually use. Start with the free versions or trial periods to validate your process, then upgrade as your sales volume justifies the cost.
Price Monitoring and Sourcing
Finding deals before competitors is the core of online arbitrage. You need tools that track price drops, monitor competitor listings, and alert you to profitable opportunities across retailers. CamelCamelCamel tracks Amazon price history and sends alerts when items drop to your target price—critical for knowing if a deal is genuinely rare or cyclical. Keepa provides similar price tracking with graph data going back years, so you can spot seasonal patterns and avoid buying during temporary dips. Both let you set threshold prices and get notified automatically, saving you hours of manual checking daily.
Inventory Management
When you’re buying from multiple retailers and selling on multiple channels, inventory becomes complicated fast. You need a system that tracks stock levels, alerts you to low quantities, and prevents overselling. Sellfy and Inventory Labs both sync inventory across sales channels—when you sell one unit on Walmart.com, your stock updates everywhere automatically. This prevents the expensive problem of selling the same item twice. These tools also let you set reorder points, track supplier lead times, and see which products turn fastest, so you know what to prioritize buying.
Multi-Channel Selling and Order Management
Most online arbitrage sellers operate across Amazon, eBay, Walmart Marketplace, and their own store. Managing orders, refunds, and customer inquiries separately across all these platforms is unsustainable. Sellfy and Shopify both centralize order management—you receive all orders in one dashboard, print labels in bulk, and sync fulfillment status back to each marketplace. RepricerExpress automatically adjusts your prices to stay competitive, which matters when you’re competing against dozens of other sellers offering the same product. The time savings alone justifies these tools once you’re doing $3,000+ in monthly sales.
Accounting and Financial Tracking
Online arbitrage has tight margins—often 15-30% gross profit before fees and shipping costs. You need precise accounting to know which products are actually profitable after all expenses. Wave is free and lets you track revenue by sales channel, categorize expenses (shipping supplies, fees, returns), and generate profit reports monthly. As you scale past $10,000 monthly revenue, QuickBooks Online becomes worth the cost because it integrates with your bank account and inventory tools, giving you real-time profitability by product and channel. Without this visibility, you might be selling items that look profitable but lose money after factoring in all fees.
Shipping and Fulfillment
Your shipping cost directly impacts profit margins. Negotiating carrier rates and printing labels efficiently can save you 5-15% on shipping expenses. Pirate Ship gives you discounted USPS rates and integrates with most ecommerce platforms—you can print labels in bulk and track all shipments in one place. For heavier items or larger volumes, Shippo compares rates across USPS, UPS, FedEx, and DHL, letting you automatically choose the cheapest option for each package. Both tools integrate with your inventory system so tracking and fulfillment happen seamlessly.
Communication and Customer Service
Customers contact you through Amazon messages, eBay messages, email, and potentially your website. Managing these separately creates missed messages and slow response times, which hurt your seller rating. Zendesk consolidates all customer messages into one inbox with automated routing and canned responses for common questions. Help Scout is lighter-weight and less expensive, offering similar consolidation without the complexity. Both let you track response times, assign tickets to team members (if you hire help), and maintain consistent, professional communication.
Spreadsheet and Data Analysis
You’ll analyze which products sell fastest, which suppliers are most reliable, and where your margins are best. Google Sheets is free and sufficient for tracking product performance, supplier costs, and profit calculations. You can pull data from inventory tools and create pivot tables to identify trends. If you’re processing hundreds of SKUs, Tableau or Data Studio (free) can create dashboards that show profitability, velocity, and inventory health at a glance.
Email and Supplier Communication
You’ll manage correspondence with suppliers, negotiate bulk discounts, and handle customer refund requests via email. Gmail with labels and filters handles this adequately when you’re starting, but once you’re doing 50+ supplier and customer emails weekly, Outlook or a CRM like HubSpot (free tier) lets you track conversations, schedule follow-ups, and maintain templates. This prevents dropped conversations and ensures you follow up on supplier quotes within 24 hours.
Tax and Compliance
Sales tax, income tax, and business registration vary by state and sales channel. TaxJar automatically calculates sales tax obligations across marketplaces and helps you file returns—essential once you exceed $10,000 annual sales. Stripe Tax and similar tools can also handle this if you’re selling primarily through your own website. Starting with spreadsheet tracking of sales by state is acceptable initially, but as volume grows, tax software prevents expensive mistakes.
Free vs Paid Tools
Start with free versions: CamelCamelCamel, Wave, Pirate Ship, Google Sheets, and Gmail handle the absolute fundamentals. These cost nothing and work for your first 100-200 sales. This validates your process before you commit money to paid tools.
Upgrade to paid tools when they directly impact revenue or save you 5+ hours weekly. Inventory Labs (around $99/month) makes sense once you’re tracking more than 50 SKUs across multiple channels. Sellfy ($99-299/month) becomes essential when manual order management takes 10+ hours weekly. Order tools based on what’s slowing you down, not on a pre-set budget. A tool that saves you 10 hours weekly at your time value is worth $500/month; one that saves 30 minutes is not.
The Minimum Tech Stack to Launch
- CamelCamelCamel or Keepa for price monitoring and deal alerts—you cannot source profitably without knowing price history.
- Pirate Ship for shipping labels and cost tracking—starts free and saves money immediately.
- Wave for accounting and profit tracking by product—prevents flying blind on actual profitability.
- Google Sheets for inventory and supplier tracking—free, accessible, sufficient until you exceed 500 SKUs.
- Gmail for customer and supplier communication—adequate with good label organization until volume hits 100+ daily emails.
This five-tool stack costs roughly $50-100 monthly and handles sourcing, fulfillment, accounting, and communication. Add Sellfy or Inventory Labs once you’re selling on three or more channels and manual syncing takes more than 5 hours weekly. Add QuickBooks once monthly revenue exceeds $10,000 and tax tracking becomes complex.