Oikotie Upgrade Chrome Extension
Oikotie Asunnot is the biggest Finnish online marketplace for selling or buying houses/apartments. When buying a house you might get an advantage if you know when the ad was placed. You might know for how long the usual broker contracts last, so you can do a low ball offer close to when the contract is ending, that is usually when the broker has most interest in closing the deal since it might be the last offer before they loose their client. Also private sellers that have had the same ad up for months might be more willing to settle for a lower price.
Oikotie is not displaying the information when the ads are placed so I built a Chrome extension for displaying that. It's called Oikotie Upgrade - extension. It will also add a link to Asuntojen Hintatiedot which tells you at what price houses has been sold in the area earlier.
Here is an example (right bottom corner):
