OpenSeinBot

What we fetch

The listing page for your rentals, and nothing else. No detail pages for properties we already know, no images, no forms, and no paths you have excluded in robots.txt . What we keep is the address, the asking rent, the number of rooms, the floor area and the link to your page.

What we do not do: copy advert copy, store photos, rebuild your page or apply on anyone's behalf. Anyone who wants to apply is sent to your site. That is where it happens, and that is where we want to keep it.

How often

That depends on how quickly new listings appear on your site, and it is fixed per host. In practice that is once every three minutes for an estate agency, and once every twenty to thirty seconds for a landlord who publishes all day. We always start slow and only speed up once a stretch without errors shows that we can.

We hold ourselves to three things, and they are rules in the code rather than intentions:

• One request at a time. Never two at once to the same server.
• If there is a Crawl-delay in your robots.txt, that is the floor. Even if it is higher than what we would pick ourselves.
• A 429 or a Retry-After means stopping and coming back later, not trying again.

How to keep us out

Three ways, from soft to hard. All three work.

1. robots.txt

We read it at every start and at least once a day, and we do what it says.

2. An email

Send a message to bot@opensein.nl from an address on your own domain. We switch your source off and your properties disappear from the site. That is permanent: an opt-out stays in place, including after a new version of our software.

3. Block us

That works too, and we will notice. We never try to get around a block: no other name, no rotating addresses, no browser pretending to be a visitor. If you say no, it is no.

Why we do this

Free-sector rentals go to whoever applies first. Look at the wrong moment and the place is gone. We read what is on your own site and send people to you, instead of to a middleman by way of an aggregator. Paying never buys priority here: everyone gets the same alert in the same round.

If something we show from your site is wrong, or you would rather we read a different address, we would like to hear about it at the same email address.

More about the service is on the about page , and what we keep about visitors is in the privacy statement.