We stayed at Leon's flat for 5 nights with my family. The flat has really a very good location: it's near KuDamm if you are interested in shopping and has U-Bahn station close by, so you can get to Alexanderplatz within 20-25 minutes. There is also a free parking place in backyard. The flat is bright and fully equipped, there are even some food and beer in fridge. We had early check-in and Leon was friendly.
However next day I noticed that sofa was broken (sleeping comfort was not reduced, but the host didn't inform us), bed linens were partly missing and had some stains, white marble floor also looked a bit dirty. I wrote a message to Leon with these remarks, but he replied me quite rude that I'm very demanding for what I pay, that I can leave his apartment and that about stains he's sure I "won't die from it" (Leon's style is kept, all messages are stored in Airbnb and can be provided on request).
Next day a neighbour (from downstairs) came and asked to move chairs quietly, because they are made of metal and are very loud on marble floor. I highly recommend owner to put a carpet under the table. Otherwise you really should use the flat only for sleep, as neighbours are very sensitive.
During our stay we also noticed ants, which probably came from balcony (I made photos as a proof).
So, for what we paid (54EUR/per night) the flat was good, but the service provided by the host was satisfactory, as it's rather strange when with cleaning fee of 30EUR there are dirty or missing linens.