Inventory software for resellers: spreadsheet or dedicated tool?

Inventory management software for resellers tells you, for each item, what it cost you, where it's stored, where it's listed and how much it earned you. A well-built spreadsheet is enough up to around a hundred items in stock and a single sales channel. Beyond that, or as soon as you sell across several accounts, a tool linked to your sales prevents mistakes and oversights.

You'll find the features that really matter, a spreadsheet template to set up tonight, and the signs that it's time to change tools.

Why does a reseller need to manage stock?

Because a reseller doesn't make money on what they sell, but on the gap between what they buy and what they sell. Without tracking, you know your turnover, not your margin.

Three problems show up quickly without stock management:

• You can't find the item you sold. It's in a bag, in a box, in the car. Every search costs ten minutes and sometimes a late dispatch.
• You don't know what's sitting idle. Pieces bought six months ago tie up your money without you noticing.
• You work out your margin by guesswork. The purchase price is forgotten, postage or bump costs aren't counted anywhere.

There's also an administrative reason. In France, if you're a micro-entrepreneur selling goods, you must keep a sales ledger and a summary register of your purchases, according to Service-Public's official page on a micro-entrepreneur's bookkeeping obligations. Rules differ elsewhere, but clean stock tracking gives you that kind of register almost for free.

Which features are essential in inventory software?

For a second-hand reseller, eight pieces of information per item cover the essentials. Everything else is a nice-to-have.

1. A unique reference (SKU): a short code that you also write on the label of the bag or box.
2. Purchase date and place: charity shop, car boot sale, online lot.
3. Purchase price, including your share of a lot.
4. Physical location: tub, shelf, numbered box.
5. Status: to photograph, listed, reserved, sold, shipped.
6. Sales channel and account, if you have several.
7. Actual selling price, after negotiation.
8. Associated costs: packaging, bumps, any platform fees.

With these eight columns, you can calculate margin per item, spot stock that's sitting idle and fill in your purchase register.

How do you build a stock spreadsheet in 20 minutes?

It's the most worthwhile first step, and it costs nothing. Here's the method.

Example: you buy a jacket for €6 in a charity shop, SKU V-0412, stored in tub 3. It sells for €28 after an offer. You spent €0.40 on packaging. Margin: 28 − 6 − 0.40 = €21.60. As a private seller on Vinted, you receive the item price: the Buyer Protection fee and postage are paid by the buyer, according to Vinted's price list.

Spreadsheet or inventory software: which should you choose?

The spreadsheet wins on cost and flexibility. Software wins as soon as manual data entry becomes the problem.

The tipping point isn't a precise number of items. It's the moment you stop updating your spreadsheet. An incomplete spreadsheet is worse than no spreadsheet, because it gives you a false picture of your margin.

What are the signs your spreadsheet is no longer enough?

You can diagnose yourself with four questions:

• Have you ever sold the same item twice, or sold an item you then couldn't find?
• Is your spreadsheet more than a week behind?
• Do you sell across several accounts or several platforms?
• Do you spend more than 15 minutes a day filling it in?

Two "yes" answers out of four, and software will save you more than it costs.

The cost of doing nothing is easy to put a number on. Example: 200 items in stock, 40 of them bought more than 120 days ago at an average cost of €5. That's €200 tied up that you don't see, which you could have reinvested in pieces that sell fast. A simple sort by "days in stock" brings them to light.

When your sales come from several accounts and data entry takes over, Revendor syncs your Vinted sales and purchases with your stock, calculates the margin per item and prepares the accounting export.

How should you organise your stock physically?

Good software is useless if the item can't be found. Your physical organisation should mirror your numbering.

• Numbered tubs or boxes, not unlabelled bags.
• One item per bag with its SKU written on it, for small pieces.
• A "to photograph" area separate from the "listed" area.
• A "sold, to ship" area, emptied every day.

If you list items in batches, organise your sessions by tub: photos, then listing, then putting away. You get into a rhythm and nothing gets mixed up. For listing, a good title makes a big difference: see our method for writing a title that sells.

Does stock tracking help with tax too?

Yes, indirectly. Once your activity becomes regular and aims to make a profit, your sales count as a commercial activity. Platforms also pass information to the tax authorities above certain thresholds. Our guide to declaring your Vinted sales for tax explains these rules for France.

Up-to-date stock gives you your turnover, your purchases for the period and your margin in a few clicks. That's what your accountant or the tax authorities will ask you for.