There are several business hotels around the Kintex near the Daehwa station under $100 USD.
They are quite adequate for business trip purpose. However, it is not luxurious.
* Business hotels – smaller scale of 30 – 99 room hotels and generally offer room and shower only (sometimes with a small restaurant). Similar to Inns; i.e. holiday Inn in US .
Please make the hotel reservation through major reservation companies.