Frequently asked questions: everything about Postfast
Postfast turns your photos into listings ready to publish, and tracks your resale margins. Here are straight answers to the questions we get most often: what it costs, how reliable it is, how it works and what happens to your data.
Wondering what Postfast is, whether the app is free or reliable, and how it actually works? This page gathers the questions second-hand sellers and resellers ask most often before they get started. Honest answers, with no overblown promises, so you know exactly what to expect.
Can't find your answer?
To publish listings from your own eBay account, follow the eBay connection guide. To understand how the app values an item, see how Postfast estimates resale prices.
Common questions
What is Postfast?
Postfast is a mobile app (coming soon to iOS and Android) built for second-hand resale in France. From your photos it writes a complete listing — title, description, estimated price and hashtags — then helps you keep track of your purchases, your sales, your margins and your stock. In short: other tools write your listings, Postfast runs your resale business.
How does Postfast actually work?
You take or import photos of an item, the AI reads them to work out what it is and writes the listing for you. You check it over, adjust the price or the wording if you need to, then publish. On eBay, publishing happens straight from the app; on the other platforms, Postfast opens the app you need in one tap and copies the description across automatically.
Is Postfast free?
Yes. The free plan includes 5 listing generations a month, plus 10 free when you sign up, and gives you every feature: margin tracking, CSV export and even eBay publishing. The paid plan, PostFast Plus, only unlocks volume — listing generations without limits — from €6.99/month at the launch price (soon €9.99).
Which platforms can I publish to?
Postfast covers 9 second-hand platforms: Leboncoin, Vinted, eBay, Marketplace, Etsy, Rakuten, Vestiaire Collective, La Centrale and Depop. eBay is the only one Postfast publishes to directly through an API, once you have connected your account by following the eBay guide. For the others, the app prepares and copies the listing so you can post it in seconds.
Does Postfast publish to Vinted and Leboncoin automatically?
No, and we would rather say so plainly. eBay is the only platform that allows direct publishing through an API. On Vinted, Leboncoin and the rest, Postfast opens the app in one tap and pastes the description for you: you stay in control of the final post, without retyping anything.
How reliable is the price estimate?
The estimate combines the AI with comparable items taken from live eBay listings: a solid starting point, not a guaranteed truth. That is why the app gives you links to real sales (sold items on eBay, plus Vinted and Leboncoin) so you can check the right price yourself. You can also read in detail how resale price estimation works.
How does Buying mode work (valuing an item before you buy)?
Buying mode lets you photograph an item before you buy it, to estimate its resale value and your potential margin against the asking price. Postfast does not tell you what to buy or where: it gives you the real market data so you can decide with your eyes open. Handy at a car boot sale, a flea market or a consignment shop.
Can I track my margins and my profitability?
Yes, and it is the heart of Postfast. By tying a sale back to its purchase, the app works out your real net margin and ROI, splits the cost of a job lot across items in proportion to their value, and flags dormant stock as well as anything sold at a loss. You even get a best-and-worst ranking of your purchases: see how to work out your resale margin and ROI.
Can I customise the listings the AI writes?
Yes. You choose the tone, whether to use emojis and hashtags, your own intro and sign-off, and your Vinted username. Every listing stays fully editable before you publish: title, description, price and hashtags can all be reworked in a moment.
How much does PostFast Plus cost?
PostFast Plus is €6.99/month at the launch price (soon €9.99). It only unlocks volume, with listing generations without limits. Every other feature — CSV export, eBay publishing, margin and stock tracking — is already in the free plan.
Is my data protected (GDPR)?
Your data is hosted in Europe (Supabase infrastructure, Frankfurt region), with secure authentication and isolation between users. Postfast is built for the French market and designed to comply with the GDPR. You can export your data to CSV, import your purchases, or ask for your account to be deleted at any time.
When will Postfast be available?
The app is not on the stores yet: it is being prepared and is coming soon to iOS and Android. In the meantime, you can go through everything it does here on the site, so you are ready on launch day.
Ready to sell faster?
Postfast writes your listings with AI and tracks your margins. Coming soon to iOS & Android.
Discover PostfastGot a question? Email us at hello@postfast.fr.