We really enjoyed our time in Berlin, and overall were happy with this accommodation. There were a number of really good things. There were also some things that were disappointing, although all could be easily fixed.
Good things:
1. Alan met us at the apartment and spent a fair bit of time providing us with useful information about it, the local neighourhood and the city more generally - much appreciated.
2. The apartment had everything we needed - in particular for people travelling with young kids, it had a high chair and a box of toys/books, which were great.
3. Close to transport, fairly easy to get to most places of interest
4. Fairly nice neighbourhood
Things that could be improved:
1. Cleanliness - the floors and shower curtain were very dirty and, somewhat bizarrely, the kettle was full of vinegar (!?!).
2. Some low quality things in the house which reduced comfort a bit -pillows were awful and the kitchen chairs quite rickety (one was actually broken or not assembled correctly).