How to Track Inventory for Resellers: A Simple System That Scales

If you sell sneakers, vintage, electronics, or anything in between, the difference between a profitable month and a chaotic one usually comes down to one thing: knowing what you actually have.

The five fields every reseller needs

Forget the 20-column mega-sheet. At minimum, track:

• Name — what it is, written how you search for it
• SKU — your own code, not the brand's
• Purchase price — what it cost you all-in (including shipping to you)
• Sale price — your target list price
• Quantity — how many you have right now

Everything else (category, tags, notes, photos) is optional polish — useful, but not required to run the business.

Use a consistent SKU pattern

Your SKU is the spine of the system. Pick a short, predictable pattern and stick to it. A simple format that works for most resellers:

CATEGORY-BRAND-NNN — e.g. SNK-NIKE-014, VTG-LEVI-022.

Three letters per segment, three-digit counter. Searchable, sortable, and you'll never accidentally collide with the brand's own SKU.

Photograph before you list

One clean white-background shot per item, taken the moment it enters inventory. Future-you will not want to dig the item back out of a bin to reshoot it for a new platform.

Update quantity at the moment of sale

Not at end of day. Not "when I get a chance". The moment money changes hands. This is the single habit that separates resellers who know their numbers from those who guess.

When to graduate from a spreadsheet

The rough crossover is around 50–100 active SKUs. Past that, manual updates eat hours per week, photos slow your file to a crawl, and you'll miss low-stock moments. We wrote about this trade-off in detail.

The bottom line

A good inventory system isn't fancy. It's five fields, a consistent SKU, and the discipline to update at the moment of sale. Whether you do that in a sheet or in Inventra, the habits are what make it work.