The location of this apartment was one the best part of our whole stay. You're literally in the heart of the city, with all the public transportation needs that you need. Mauer Park is literally in front of the apartment. Every single meal that you can think of from around the world is at your doorstep. The Berlin Wall memorial (at least one part of it) is just behind the apartment.
The apartment itself is lovely, it has all that one needs and a fast wifi connection. We went when it was exceptionally hot there, and I messaged Juan about perhaps having a fan, and one was ordered and delivered to us on the day which was lovely. In fact communication with Juan was great, he responded within minutes.
The apartment was clean enough, although we did find a few dusty places when we first arrived. But this was sorted out with a quick vacuum, which is provided. This culd just be because the apartment is street facing though. The towels were clean, but we found a lot of them to be a little bit damp, which I assume meant they were not dried out properly. Again, not a huge deal as a rack was provided in which we dried them out ourselves by the window.
All in all a lovely stay, I would highly recommend it, and Berlin itself is great value for money for a world city.