In compliance with the General Data Protection Regulation (GDPR EU 2016/679) and applicable European data protection laws, we inform you transparently and in detail about how we process your personal data on this website.
All interactive simulation tools on this website (Buy or Rent, New vs Existing Property) execute all mathematical calculations 100% locally in your browser memory (client-side). Under no circumstances are your financial figures, income, savings, or purchase assumptions sent, transmitted, or stored on our servers or external databases.
The data controllers responsible for personal data collected on this website are Thomas Lefebvre and Bárbara Castillo Rico (co-authors of the book). For any questions regarding your data protection or to exercise your rights, you can reach the data controllers through this official website: https://www.mieux-decider-immo.fr.
We collect only strictly necessary data: (a) Subscription form & PDF extract download: email address, preferred language, consent timestamp, anonymized IP address (masking the last octet prior to database storage), and lead source. (b) Browsing and analytics data: pseudonymous cookie identifiers (_ga), aggregated interaction events, and campaign parameters (including visits via printed book QR codes), strictly subject to prior explicit consent.
We process personal data for: (a) Managing the delivery of the book PDF excerpt and informative announcements regarding the book launch and editorial updates. (b) Ensuring technical functionality and security of the website. (c) Performing aggregated statistical analysis of website engagement and chapter consultations via QR codes. (d) Documenting and maintaining an audit log of user consent in accordance with the principle of accountability.
The applicable legal bases under Art. 6.1 GDPR are: (a) Explicit user consent (Art. 6.1.a) for email notifications and analytics cookies. (b) Legitimate interest and execution of the requested service (Art. 6.1.b and 6.1.f) for technical website navigation and simulator operations. (c) Compliance with legal obligations (Art. 6.1.c) for maintaining auditable consent records.
Data is retained for the following periods: (a) Subscriber emails: until you unsubscribe or withdraw consent, or when editorial update communications conclude. (b) GDPR Consent Registry: retained in a blocked state for 3 years to comply with statutory limitation periods for legal accountability. (c) Google Analytics telemetry: retained for a maximum of 14 months with IP anonymization.
We never sell, rent, or trade your personal data with third parties for commercial purposes. We work with trusted service providers acting as Data Processors: (a) Google Ireland Limited / Google LLC (Google Sheets API for consent records and Google Analytics 4), covered by the EU-U.S. Data Privacy Framework and European Commission Standard Contractual Clauses (SCCs). (b) Vercel Inc. (cloud infrastructure and web hosting), certified under the Data Privacy Framework. Purchases through distributor links (Amazon, Fnac, Dunod) occur entirely on their platforms under their respective independent privacy policies.
You have the right at any time to: access your personal data; rectify inaccurate or incomplete data; request erasure ('right to be forgotten'); request restriction of processing; object to processing; and obtain data portability in a structured format. You also have the right to withdraw your consent at any time without affecting past lawful processing.
You can exercise your rights free of charge by submitting a request to the data controllers specifying the right you wish to exercise (access, rectification, erasure, restriction, objection, or portability). If you believe your rights have not been respected, you have the right to lodge a complaint with the competent supervisory authority: the French CNIL (www.cnil.fr), the Spanish AEPD (www.aepd.es), or the data protection authority of your EU member state of residence.
We apply robust technical and organizational security measures: full HTTPS/TLS communication encryption, IP anonymization and masking prior to persistence, strict server-side schema validation (Zod) with payload restrictions (10 KB), and access control restricted to secure service accounts.
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