There is no one to check you in at this property. There will either be a piece of paper on a desk with your name, room number, and the lock passcode for said room (!!!), or you will have to contact the management through an iPad on the wall of the "Front Desk". Both of these methods present an extreme security risk, as there is no lock on the entrance, meaning anyone can enter, look at the message history on the iPad and see any guest's room number and passcode.
On a related note, contacting the management can be extremely difficult as they do not seem to be consistently monitoring these messages. This was evidenced by a number of guests having left questions in the messages, only to be answered hours later, or not at all.
As for the room quality, you're bound to find somewhere nicer for the same or less money.
The "mattress" was essentially a box spring.
Overall cleanliness was average at best. The shower and the toilet are in the same room, which is fine in and of itself, as I am told this is common in South Korea. However there is zero separation, meaning that the toilet paper is liable to get wet...
Cannot recommend this property on the grounds of the insecure check-in alone, and it has no other redeeming features.
Even if you just need a place to crash, you'll no doubt be able to find a nicer place in the same area for less money.