You bought a vintage camera at an estate sale three weeks ago. You're pretty sure you listed it somewhere, but was it eBay or Mercari? How much did you pay for it? Where did you store it? Someone just messaged asking if it's still available, and you're frantically searching through boxes trying to remember basic details about an item you own.
This chaos is the breaking point where casual resellers either implement proper tracking systems or drown in disorganization. Good inventory tracking isn't optional once you're managing more than a handful of items – it's the infrastructure that separates profitable businesses from expensive hobbies. Let's build a tracking system that actually works for your reselling operation.
Spreadsheets vs. Apps: Choosing Your System
Essential Fields Every Tracking System Needs
Setting Up a Simple Spreadsheet System
Using Barcode Scanning for Efficiency
Best Practices for Accurate Records
Scaling Your System as You Grow
Common Tracking Mistakes to Avoid
The Payoff of Good Tracking
Both spreadsheets and dedicated apps work well for inventory tracking. Your choice depends on your technical comfort, budget, and specific needs.
Spreadsheets (Google Sheets or Excel) are free, infinitely customizable, and accessible from any device. You control exactly what information you track and how it's organized. Formulas can automatically calculate profits, track expenses, and flag items sitting too long. The learning curve is minimal if you have basic spreadsheet skills.
Drawbacks include manual data entry for everything, no built-in barcode scanning, and potential for human error when typing information. As inventory grows beyond 200-300 items, spreadsheets can become unwieldy without good organization.
Inventory apps like Sortly, Nest Egg, or reseller-specific tools offer built-in features like barcode scanning, automatic calculations, and photo storage. Many sync across devices and backup data automatically. Premium apps include analytics showing what's selling, profit margins, and inventory turnover rates.
Drawbacks include monthly subscription costs ($5-20/month typically), less customization flexibility, and learning curves for new software. You're also dependent on the app continuing to exist and maintain features.
The hybrid approach works well: use spreadsheets for financial tracking and quick reference, while using apps for physical inventory location and barcode scanning. This combines free tools with specialized features.
Regardless of your chosen system, track these critical data points for every item.
Item identification: Unique item number (001, 002, etc.), brief description, and category. This helps you locate and reference items quickly.
Financial data: Purchase price, intended selling price, actual selling price, platform fees, shipping costs, and net profit. These numbers show whether you're actually making money.
Dates: Date acquired, date listed, date sold. This reveals how long items sit and helps identify slow-moving inventory needing repricing.
Location: Specific storage location – "Shelf 3, Bin B" or "Closet, top shelf, red bin." Without this, you'll waste hours hunting for items buyers want.
Listing information: Platform listed on (eBay, Poshmark, Facebook), listing URL or ID number, and current status (unlisted, active, sold, returned).
Source information: Where you acquired the item (estate sale, thrift store, garage sale) and any relevant notes. This data helps identify your most profitable sourcing locations.
Condition and notes: Size, color, flaws, missing pieces, or anything affecting value. This prevents relisting research and helps with customer questions.
Start with Google Sheets for free cloud access from any device. Create these column headers across the top:
Item #
Description
Category
Purchase Price
Selling Price
Platform
Date Acquired
Date Listed
Date Sold
Location
Status
Notes
Net Profit
Use dropdown menus for consistent data entry. For "Status" create options: To List, Active, Sold, Returned. For "Category" list your common types: Clothing, Electronics, Home Goods, etc. This prevents typing variations that mess up sorting and filtering.
Color-code rows by status: gray for unlisted items, green for active listings, blue for sold items. Visual cues make scanning easier.
Use formulas to calculate automatically. In the Net Profit column, use: =Selling Price - Purchase Price - Fees. This shows real profit without manual math.
Create filters to view specific subsets: all unlisted items, everything purchased in November, items listed over 90 days, or all active eBay listings.
Make a habit of updating immediately. When you acquire items, log them before storing. When listing, update status and date right away. When items sell, mark sold immediately and record final prices.
Barcode scanning dramatically speeds up research and tracking for items with UPCs or ISBN numbers – books, electronics, toys, and packaged goods.
Apps like ScoutIQ, Scoutify, or the Amazon Seller app scan barcodes and instantly show current market values, sales rank, and pricing history. This helps with sourcing decisions and initial pricing.
For tracking, apps like Sortly allow scanning barcodes to add items to inventory and quickly locate them later. Scan the item, take a photo, add location and price info, and you're done in 30 seconds.
Build a system: scan items immediately when acquiring them, store the barcode info in your tracking system, and use barcodes for quick verification when locating items for shipping.
For items without barcodes, consider printing and affixing QR codes or numbered labels that link to your digital records.
Consistency beats perfection. A simple system used religiously is better than a complex system used occasionally.
Update in real-time, not "later." Later becomes never, and you'll forget critical details. Log items as you acquire them, update listings immediately when posting, and mark sales the moment they happen.
Take photos for everything and store them with inventory records. Photos help you remember items, assist with customer questions, and provide proof of condition if disputes arise.
Backup your data weekly. If using spreadsheets, download copies or ensure cloud backups are working. If using apps, verify they're backing up data automatically.
Review inventory monthly. Scan through records looking for items listed 60+ days, unlisted items that need attention, or data entry errors to correct.
Use item numbers religiously. Write item numbers on physical labels attached to items or their storage containers. This creates foolproof connections between physical items and digital records.
Start simple when managing 10-20 items. Basic spreadsheets with essential fields work fine for beginners.
At 50-100 items, invest time in better organization. Add more detailed tracking fields, create better storage systems, and consider specialized apps.
Beyond 200 items, you need robust systems. This might mean paying for premium inventory apps, using barcode scanning extensively, or hiring help for data entry.
As you scale, categorize more specifically. Instead of "Clothing," break into "Women's Tops," "Men's Pants," "Kids' Shoes." Specific categories enable better analysis of what's profitable.
Consider accounting software integration when reselling becomes serious income. QuickBooks or Wave can connect with inventory systems for seamless bookkeeping.
Don't skip the system because you "don't have that many items yet." The habit matters more than inventory size. Build good practices early.
Never rely on memory alone. You will forget what you paid, where items are, or whether you listed something. Write it down.
Don't create overly complicated systems you won't maintain. Tracking 50 data points per item sounds thorough but becomes burdensome. Track what matters, skip the rest.
Avoid multiple unconnected systems. Having inventory lists in three different places guarantees confusion and errors. Choose one system and stick with it.
Don't neglect data cleanup. Periodically archive sold items into separate sheets or files so your active inventory views stay clean and manageable.
Proper inventory tracking provides clarity about your actual profitability, prevents lost items and wasted money, enables data-driven decisions about what to source, saves hours of frustrated searching, and makes tax time infinitely easier with organized records.
The resellers making real money aren't necessarily sourcing better items – they're tracking everything meticulously, learning from their data, and making informed decisions. Your tracking system is the foundation everything else builds upon. Get it right, and reselling becomes manageable and profitable. Skip it, and you're flying blind with money tied up in items you can't even find!