I stayed in the Hotel Adina Hauptbahnhof in a 3-bedroom apartment style hotel suite. It was an awesome experience and was somewhat nervous about booking it at first. However, it turned out to be a great accomodation and I thoroughly enjoyed having a base for 6 travelers.
Check-in went very easy and the front desk staff were amazing. Although I speak a little German, their English was flawless and they were accomodating in so many ways.
We decided to walk to the hotel from the Hauptbahnhof. It was a very easy walk. Like other reviews state, there is construction happening all over but it's happening all over Berlin and isn't a reflection of the hotel. The location towards the Hauptbahnhof makes it an ideal location in my opinion. 6 people with suitcases had no problem walking the short distance. I enjoyed that the hotel is in somewhat of a residential area, as some parts of Berlin are too city-like. There are several grocery stores around the area, and some restaurants. The train station is also open 24/7 if anything is ever needed.
I ate at the restaurant for dinner and lunch one time. The prices are comparaible to the rest of Berlin and the service was good.
Having a kitchen, living room, laundry facilities, and large bedrooms/bathrooms was much needed for our group. We used the hotel as a way to regroup as it was the halfway point of our trip. It was well worth it and I highly recommended it!