Zillow collects extraordinarily revealing behavioural data: search filters (price range reveals income), saved homes (neighbourhood reveals race and class preferences), school district browsing (reveals children or family plans), mortgage calculator inputs (reveals exact financial capacity), "recently sold" browsing (reveals whether you're selling), and rental searches (reveals financial constraints). Combined, a Zillow browsing session reveals more about your life circumstances than almost any other app: you're getting divorced (searching for smaller homes), you're having a baby (searching near good schools), you're being relocated (searching in a new city), you lost your job (switching from buying to renting). Zillow shares data with real estate agents, mortgage lenders, insurance companies, and advertisers. Your home search is a life change detector. Every filter you set describes your financial capacity, family situation, and future plans to Zillow's advertising partners.

realestate.com.au collects property search data that reveals life circumstances with precision: price range filters reveal income and borrowing capacity, suburb searches reveal where you want to live (and where you can't afford), saved properties reveal aspirations, mortgage calculator inputs reveal exact financial capacity, and inspection bookings reveal serious intent. Combined, a browsing session tells REA Group whether you're upgrading (bigger house, better suburb), downsizing (divorce, empty nest), relocating (job change), or in financial distress (switching from buying to renting). REA Group sells leads to real estate agents and mortgage brokers -- your search becomes a product sold to the people who want to sell to you. The platform is majority-owned by News Corp (Rupert Murdoch). Your property search data sits within the same corporate ecosystem as The Australian, Sky News, and news.com.au. Australia's housing search and Australia's largest media company share an owner.

In April 2026, the OAIC found 2Apply breached the Privacy Act by collecting excessive personal information from rental applicants — gender, student status, citizenship, visa expiry dates, vehicle details — none of which is necessary for a tenancy application. The OAIC also found 2Apply used manipulative design patterns including "biased framing" and bundled consent to pressure tenants into sharing more data than required. In a rental market with extreme power imbalance — where applicants compete for scarce housing — refusing to provide excessive data means risking your application. An estimated 57 third-party rental tech platforms operate in Australia, creating a massive dataset of tenants' personal, financial, and identity information.