Check-in was a breeze. The apartment staff text me the day before our arrival with clear instructions on what to do when we arrived. They even included their wifi information so I could text them from outside the building without cell service!
The entire building has been renovated and is accessed via an access code, same code for you room. We were on the second floor, in 2A I believe, and there is a small but reliable elevator. The room itself was huge, especially for what I've grown accustomed to traveling Europe. There was a very large bathroom with a rain shower, toilet and bidet. The apartment provided us with both hand and body towels for the three of us, but they weren't changed during our stay (I read you have to stay longer than four days for maid service). They brought us an extra, single bed as there were three of us staying in the room and even then we still had room to be comfortable in the apartment. We really appreciated the small kitchenette and the refrigerator and freezer for leftovers and chilling wine.
We stayed in mid-April and I woke up very hot the first night so I opened all of the windows. Be warned - if you are a light sleeper, leave the windows and the window covers closed! This neighborhood gets very loud at night but if you keep the windows closed it's fine. The apartment also provided several fans but we did not use them.
Check-out was simple as well, we simply closed our door behind us and that was it. We would definitely stay here again