Gather the tenancy agreement, deposit receipt, check-in and check-out reports, dated photographs, rent records and all messages about the deduction. Ask the landlord or agent in writing for an itemised explanation and supporting invoices, and compare each claimed cost with the evidence and normal wear and tear. Keep a clear timeline of events and records of any steps you took to report or fix damage. If you cannot resolve the issue, you can consider the RTB dispute resolution process; the outcome depends on the individual evidence and tenancy facts, so check the RTB’s current guidance or seek advice from a qualified professional.