If you wish to mail them, be sure to call them and ask what their procedure is for returning the documents to you. Although the school will pay for your rent, teachers are responsible for paying their own utilities. It is difficult to say exactly how much utilities may cost because different type of housing has different utilities costs. It also depends on other variables based on what you use on your house such as an air conditioner, TV cable, Internet connections, or telephone lines. 10,000 - 20,000 Bills generally come monthly and arrive at the apartments by the 20th or 25th of the month.
Exceptions are water and electricity bills that come quarterly.
Utilities are your responsibility so if you don't receive a bill by the 10th of the next month, you should notify your school immediately. It is Korean law that foreign employees can only legally work for the employer that is sponsoring their visa, unless otherwise permitted by the Korean Immigration Office. In other words, you cannot work for anyone or teach private lessons unless permitted by the Korean Immigration Office. Deductions are withheld automatically from your monthly salary. You pay slip will be written in Korean, but if you want to understand exactly what everything is, you can ask your academic director to explain everything to you.