This apt. is very good! Yoni - the owner - is well organized, nice and very helpful. You'll get perfect directions. So it's totally easy to find the place without being able to read korean.
The place is clean in a normal way. It's well located and next to a subway station. A big supermarket is near. We can recommend the massage place in the house.
The 2nd floor of the apt has a very low ceiling. You won't be able to stand uprigth. To us it was just storage. So it wasn't a problem.
The area is nice. You'll get everything you need: Good coffee shops, restaurants. Even a very good running path (next to the Han river) is near.