We do our research on this very thoroughly to be sure that your salary is at the industry average or better. Generally, the monthly salary for a first time teacher with no experience or certification is about 2-2.1 million won. This amount goes up depending on the type of degree you have and any other certification you've aquired (TEFL, TOEFL, TESOL, etc.). The increments for each usually amount to 100,000 won/month.
Having a degree in Education, CELTA, or TESOL is preferred and should get you a little more money but a degree in any discipline is acceptable.
WATCH OUT FOR A RISING TREND IN JOBS POSTING HIGH SALARIES!
It's unrealistic that a school could pay a new teacher much more than the industry average. It's most often "creative advertising" when some recruiters or employers are posting salaries of 2.5 million won or more per month to start, and what they are not telling you right away is that they are not providing RENT-FREE housing at that rate of pay. They will usually provide the key money (deposit) if you choose to find your own accomodations, but you'll have to pay between 350,000-600,000 won per month for rent (depending on the size and location). Some employers will tell you that your salary includes housing, though they may not tell you that it is NOT rent-free and they WILL deduct the monthly rent from your salary.
Another reason we've found is that the school might have a very high turnover of teachers, therefore they must advertise a higher salary to compete in the ESL advertising market.
Please be careful and ALWAYS ask specifically about this when applying for a job with anyone. Find out EXACTLY what you will be taking home each month after all deductions.