My first time staying in a hotel in Berlin and had a great experience. The reception staff are…read moresuper friendly and helpful and facilitated an early check in for me after I arrived early. I also got a "bid what you want" upgrade to a room on a high floor overlooking the street.
The layout for the 2nd tier room is small but perfectly functional for a single traveler or couple, and I loved the thoughtful touches like a small chair in the bathroom, umbrella in the room with a holder, and hooks on the wall near the closet.
The (nonalcoholic) drink minibar is free to take from and refilled daily which is another plus! And they had small chocolates that were refilled daily as well. I didn't partake in any breakfast or other food, but it did look good when I passed by.
The garden area outside is nice to relax or work in. The hotel itself is on a quieter street but near many different modes of public transit - tram, bus, subway. The front desk warned me about needing coins for the tram / bus and was happy to exchange some bills into coins for me every morning as well. Not many taxis passing by but the front desk will call one for you very quickly if you ask. There are also bikes and scooters you can borrow.
Overall I had a great stay and would have loved to stay longer! I had to move to another hotel for work, but wish I could have stayed at the i31.