The resale management software that runs your stock and your margins

Dozens, sometimes hundreds of items to keep on top of: Postfast writes your listings back to back, publishes to eBay and shows you what earns, what sits still and what you really make.

Running dozens of items without losing sight of any

When you resell in volume — car boot sales, clearance buys, consignment shops — the real work starts after the photo. Listings have to go up fast, and you need to know what each item cost, what price it goes out at, and above all what earns against what sits in stock. A spreadsheet always ends up overflowing, and the platforms never talk to each other.

Postfast brings the two halves of the job together: writing listings from photos and tracking real profitability. One place for your purchases, your listings and your sales, built for the French second-hand market. That is the whole difference: other tools create the listing, Postfast runs the business around it.

Writing your listings back to back

Photograph an item, and the AI writes the title, the description and the hashtags, and suggests a price. You do it again, item after item: this tool for the professional reseller is built for the pace of volume, not for a one-off sale.

1

Photo

Take your photos. The AI identifies the item and reads what is visible: brand, model, condition.

2

Listing

Title, description and hashtags written in seconds, and editable before anything goes live.

3

Publishing

On eBay, direct publishing through the API. On the 8 other platforms, the app opens in one tap and copies the description for you.

Worth knowing.

Only eBay publishes directly, through an official connection (see the eBay guide). On Vinted, Leboncoin, Depop and the rest, Postfast prepares everything and pastes the description in one move — you keep control of putting the listing live, nothing goes out automatically on your behalf.

Tracking stock, sales and net margins

Every purchase becomes a line of stock. When an item sells, you link the sale to its purchase: Postfast then works out the net margin — platform fees and outside costs deducted — and the real resale ROI, not a theoretical estimate. This resale stock tracking is what turns a hunch into a figure.

To follow the detail of the calculation and firm up your figures, see how to work out your margin and resale ROI.

Splitting the cost of a lot in proportion to value

You buy a job lot for €120: a console worth 80 and eight games worth 15 each. Splitting the cost into equal shares would skew every margin you have. Postfast splits the purchase price in proportion to the estimated resale value of each item.

The result: the console carries a bigger share of the cost than any single game, and each line's margin reflects reality. You stay free to adjust the split by hand if you know the market better. It is a key point in running a consignment shop and in buying by the lot, where the real cost per item quickly becomes unreadable without a tool.

Spotting what earns and what sits still

🏆

Best buys

The strongest ROI, so you know what to buy again first.

📉

Worst buys

Items sold at a loss or on a weak ROI, to steer clear of next time.

🕰️

Dormant stock

The capital tied up in what will not shift — to relist or to clear out.

These views rest on your real purchase and sales data, never on a prediction. To set a credible starting price, the app also leans on resale price estimates and eBay comparables that you can check yourself.

Importing and exporting your data

Already have a history? Import your purchases from a CSV file. Need to pull your data out for the accounts or for a separate analysis? CSV export is included in the free plan, just like eBay publishing and every other feature.

The free plan covers 5 generations a month plus 10 free when you sign up. PostFast Plus unlocks generations without limits for high-volume resellers (launch price €6.99/month, soon €9.99) — that is the only gate; the rest of the resale management software is open to everyone.

Frequently asked questions

Does Postfast publish my listings to Vinted and Leboncoin automatically?

No. Only eBay publishes directly, through an official API connection. On Vinted, Leboncoin, Depop and the other platforms, Postfast opens the app in one tap and copies the description for you: putting the listing live stays your move, nothing is published automatically in your name.

How does Postfast split the cost of a job lot across the items?

In proportion to the estimated resale value of each item, not in equal shares. A €120 lot holding an €80 console and eight games worth €15 each puts a bigger share of the cost on the console. You can adjust that split by hand if you know the market better.

Is the price estimate reliable?

It is a help and a starting point, not a guaranteed truth. The estimate combines the AI with comparables from live eBay listings. Above all, the app gives you links to real sales (eBay sold listings, Vinted, Leboncoin) so you can check the price yourself before you set it.

Can I value an item before I buy it?

Yes. In Buying mode, you photograph an item before buying it to get an estimate of its resale value and of the potential margin against the asking price. Postfast does not tell you what to buy or where: it helps you decide with real market data.

Are margin tracking and CSV export reserved for the paid plan?

No. Stock tracking, net margins, ROI, eBay publishing and CSV export are all included in the free plan. PostFast Plus only unlocks the volume of generations (without limits), built for resellers working at pace.

Read next.

Working out your margin & ROI · Estimating a resale price · Connecting eBay & publishing

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Postfast writes your listings with AI and tracks your margins. Coming soon to iOS & Android.

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Got a question? Write to us at hello@postfast.fr.