Hyun-Jung's place is very clean and comfortable, and located in a convenient location. He is great with communication and the check-in/check-out is also easy and flexible.
The only hassle we had was that we were told we could store our luggage at the apartment on the day of check-out, but this changed very last minute. Hyun-Jung tried his best to find us an alternate spot and offered to reimburse the storage fee (which is a nice gesture!). Yet, it was a hassle to be told of this change of plans and move things around in our schedule at very short notice in a foreign city.
Don't let this keep you from booking this spot. Overall, everything else was great!