Arne is a great guy, with a nice appartment in a great location in Berlin. He responds very quickly on messages, which saved us when we locked ourselves out with one of our phones still in the appartment, just before we needed to be on our train back home. He arranged for a friend to come within minutes.
The room is small, but cosy, and just what you need if you are planning on being out the door most of the time like us. You can also use the livingroom for sitting and relaxing. His cats are the cutest and will join you when relaxing.
Only point to be aware of (temporarily i guess) is that his neighbours have a baby that cries a lot, which you can hear quite well and has woken us up a few times. So if you are a sensitive sleeper probably best to bring earplugs.
But overall highly recommended, especially for cat-lovers