Assuming you haven’t wrecked the place, of course. Assuming you have taken good care of your apartment:
- Bring a camera or camcorder with you for your move-in walkthrough. Try to capture the condition of the entire apartment, empty. Put this somewhere safe.
- When you leave, clean up carefully. Plug holes, clean the bathroom, etc. You may want to hire a cleaning service yourself, as many landlords will do that, anyway, and charge you for it.
- After you have cleared out your stuff and cleaned up, get out your camera again. Do a thorough walkthrough.
- Once you are out, send your landlord a letter telling him or her exactly what you did to clear out the apartment, especially if you hired a cleaning service, and give your landlord the address where you want your security deposit sent.
If you do all this and your landlord retains your security deposit, anyway, take them to conciliation court. You have great evidence. If you return the unit to the landlord in the condition it was in when you moved in, minus normal wear and tear, your landlord should not be able to retain your security deposit.