Martin's apartment was nice and well located to visit the city. It is very close to the U-bahn and only 7 min walk to the S-bahn. The place was very clean, fully stocked (towels, products, food basics, cleaning products) and it was a good size for two people. Martin was friendly and welcomed us himself in the apartment. He was flexible with check in and check out time and gave us advice when we asked for it. We highly recommend this place for a trip in Berlin.