Help english Schools Seoul

Hi Everybody,
I am just new to the community. I have been offered a fantastic opportunity in Seoul beginning in Jan Protected content . I am a freelance contractor. I would be moving my family and would need english schools for my both daughters who are 5 and 6 years. The options that I have found on the Internet seem to be costing approx 20,000 per year minimum per child. Can anybody please advise if there any other lower cost options available that would suit a budget of say USD 1,000 per child per month.
Any advise would be greatly appreciated as this is a very important consideration in deciding on this opportunity.

Thanks in Advance
William