Apartment deposits or security deposits are payments made to the landlord to cover unpaid rent or needed repairs and cleaning costs of the apartment or house, after you move. The landlord is obligated to hold the money until the end of your lease and then use it if needed. Any of the unused money is given back to you at the end of the lease when you move out.Before you sign, make sure you read your lease carefully to understand what will happen with the deposit money when you move out. Each state or city has laws and regulations about rental and security deposits and other charges. Look those up and see how it applies to the language in the lease. Get a separate receipt when you pay the deposit. Also, if the landlord tells you he is keeping your deposit money at the end of the lease, get a detailed list of repairs and charges for which he claims he is using your deposit money. Most importantly, be proactive and read every line before you sign.