Two French property-data companies with genuinely different shapes: one is an API you provision yourself, the other is a data platform with an API attached. Here is what each actually publishes.
Yanport is a French residential real estate data company founded in 2013 by François Comer, collecting market data since 2014. It sells a full product suite — pige and prospecting tools for agents, rental studies, valuation, market analytics — with a REST API alongside it.
Stream.Estate is a data API and nothing else: 1,500+ aggregated sources, 50M+ deduplicated listings, one authenticated endpoint, self-service keys.
We have an obvious side in this, so the comparison below sticks to what each company states on its own site. Where Yanport is ahead — and on history depth, valuation and agent tooling it clearly is — the table says so.
The same real estate data, two very different operating models.
| Criterion | Stream.Estate | Yanport |
|---|---|---|
| Product shape | Data API only — no dashboard | Data platform (Agent 360, ADB 360, Invest 360, Data 360) with a REST API alongside |
| Get an API key | Self-service — sign up and create a key | Contact required: the spec states you must contact Yanport for a JWT |
| Published API pricing | €99/mo (Starter) to €799/mo (Scale); €0.01/item pay-as-you-go | 200 / 500 / 1,000 / 2,500 € per month excl. tax, no commitment |
| Free entry | €5 in credits on signup; pay-as-you-go at €0.01/item, no commitment | 15-day free trial of the application |
| Public API documentation | Public reference at docs.stream.estate | Public OpenAPI 3.0 spec, 150+ paths, no login required |
| Published source count | 1,500+ aggregated sources | Not published |
| Archive depth | 50M+ deduplicated listings | 500M historised properties, 10+ years of history, 200 TB of images |
| Geographic coverage | France (primary) and Belgium | France |
| Automated valuation (AVM) | No — market data to build one on | Yes — POST /properties/estimate, plus a valuation product |
| Rent-control data | No | Yes — rent-control endpoints and a rental-study product |
| Push notifications | Webhooks on saved searches (new ad, price change) | Consumption alerts documented; listing webhooks not documented publicly |
| Published rate limits | See docs.stream.estate | 100-request bucket at 10 req/s; 20 MB bucket at 5 KB/s; HTTP 509 on overflow |
Yanport is more transparent than most of this market on price. It publishes four API tiers openly: Starter at 200 €/month excl. tax, Essentielle at 500 €, Avancée at 1,000 € and Business at 2,500 €, all described as without commitment, with usage-based billing and configurable consumption alerts. Each tier is expressed in units of work — Starter is quoted as "400 estimations ou 50 000 biens ou plus de 9 500 indicateurs", Business as "Plus de 13 000 estimations ou plus de 1,6 million de biens".
Its documentation is open too. Yanport serves a complete OpenAPI 3.0 specification publicly, with no login, covering more than 150 paths, and it publishes its rate limits inside that spec: a 100-request bucket refilling at 10 requests per second, plus a bandwidth bucket of 20 MB refilling at 5 KB per second, with HTTP 509 as the overflow status.
What you cannot do is provision a key. The spec itself states that you must contact Yanport to obtain a JSON Web Token, and the API signup page is a lead form asking for your name, company and "mode de découverte" rather than an instant credential. Yanport's 15-day free trial covers the application, not a self-served API key.
Stream.Estate sits at the other end: sign up, create a key in your account, and start. New accounts get €5 in credits, plans run from €99/month (Starter) to €799/month (Scale), and pay-as-you-go is billed at €0.01 per item.
Yanport publishes headline figures for its own archive: 500 million historised properties, over 10 years of history, 20 TB of structured data and 200 TB of image data. That is a deep archive, and on history depth Yanport is ahead of most of this market.
What Yanport does not publish is how many sources it collects from. Its site describes "les principaux portails d'annonces payantes" and claims "la plus grosse base biens en France", but no source count appears anywhere on it — so this page does not state one.
Stream.Estate publishes the other side of that: 1,500+ aggregated sources — portals and agency sites — reconciled into 50M+ deduplicated listings, served as Hydra JSON-LD from a single endpoint.
Both are France-first. Yanport's API is built on French administrative units end to end — departments, agglomerations, cities, zip codes, quartiers, IRIS, cadastral parcels — and every coverage statement on its site is scoped to the French market. Stream.Estate covers France as its primary market plus Belgium.
Three cases where you should probably pick Yanport, or run both.
You need valuation, not listings. Yanport ships an AVM endpoint (POST /properties/estimate) and markets a full valuation product. Stream.Estate does not do automated valuation; it gives you the market data you would build one on.
You need rent-control data. Yanport's API carries a rent-control (encadrement des loyers) surface and a dedicated rental-study product. That is a French regulatory dataset Stream.Estate does not model.
Your users are agents, not developers. Yanport's suite — Agent 360 for pige and prospecting, ADB 360 for rental studies, Invest 360, Data 360 — is a set of dashboards a non-technical team can use on day one. Stream.Estate has no graphical product; it is an API your team builds on. Yanport also ships an MCP server for AI agents, currently in beta with early access on request.
The honest version of this comparison: if you want a platform, Yanport is a platform. If you want a data feed you provision in an afternoon and bill by the item, that is what Stream.Estate is.
Every statement about Yanport above comes from a page published by Yanport or from a public source, read on the date shown. Products change: if something here has gone out of date, tell us.
One API key, one endpoint, deduplicated real-time data.