Place: Christian's place is nice, clean and cosy. The room had all the amenities (including cupboards, a table etc) and the bed was very comfy. The shower/toilet was clean and good. No complaint at all.
Location: Libauer Straße is 8-10 min walk from Warschauer Straße which connects to all of Berlin by S-bahn and U-bahn. Especially the S3/S5 line takes you through the centre and to all the major attractions. It also connects to the Central Bus station at Westkreuz. You also have the tram station at just 3 min walk.
Host: But the best thing about this place is of course Christian. He was super helpful and friendly. We had to check-in very late (after midnight) but he never complained and was available for us. he also allowed us to keep the luggage at his on the last day till late which was very helpful.
5 STAR from us. :-)