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 (sellers in France) 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 second-hand reselling across 13 countries. 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.
Photo
Take your photos. The AI identifies the item and reads what is visible: brand, model, condition.
Listing
Title, description and hashtags written in seconds, and editable before anything goes live.
Publishing
For sellers in France, direct publishing to eBay through the API. Elsewhere, and on the other platforms, the platform opens in one tap: the title is copied for you, then the description the moment you need it, and you do the pasting.
Worth knowing.
Only eBay publishes directly, through an official connection, and only for sellers in France (see the eBay guide). On Vinted, Gumtree, Depop and the rest, Postfast prepares everything and copies the title, then the description: you paste them and put the listing live yourself. 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.
- Margin and ROI per item and per lot, plus your results by category and by platform
- Selling fees made visible, so the margin is never inflated
- Clear statuses: in stock, listed, sold
- Alerts that matter: sold at a loss, item due for relisting
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 (sellers in France) 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 or Gumtree automatically?
No. Only eBay publishes directly, through an official API connection, and only for sellers in France. On Vinted, Gumtree, Depop and the other platforms, Postfast opens the app in one tap and copies the title, then the description: you paste them, and 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 check the price yourself before you set it: items that actually sold on eBay, plus current listings on Vinted and the main classifieds site in your country (Gumtree in the UK, DoneDeal in Ireland).
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 (sellers in France) 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.
The app for Vinted resellers · Car boot sales & flea markets · Estimating a resale price · Working out your margin & ROI · Connecting eBay & publishing
Ready to sell faster?
Postfast writes your listings with AI and tracks your margins. Free to start, on iPhone and Android.
On a computer: open the web app, with the same account.
Got a question? Write to us at hello@postfast.fr.