I stayed at Ravouna 1906 for a week. One of my best hotel experiences. First, you do not feel like you are in a hotel, but in a large home. The building is over 110 years old and tastefully renovated. Only eight rooms. Cafe downstairs offers snacks and restaurant fare, and rooftop restaurant has one of the best views of Istanbul. The breakfast (included in room rate) is superb. Staff is very friendly and helpful and they make you feel at home. Hotel is very close to Metro and, if you do not have too much luggage, you can get to the hotel from the airport using the Metro. Far better than taking a cab, as Istanbul traffic is horrendous, despite all the new roads that have been built in recent years. In fact, I recommend you take the Metro in Istanbul wherever you go.
The rooms are spacious and comfortable, with space to relax, ample space to do work, very fast internet connection, very elegant bathrooms, well-functioning air conditioning (Istanbul is very humid). Very comfortable mattress and pillows. Small refrigerator in room. Staff provides all amenities.
Hotel is on Istiklal Street, which is open (from Tünel to Taksim) only to pedestrians during the day. You can get out of the hotel and walk comfortably without fear of cars. Also, very safe neighborhood that is full of other hotels and restaurants.
Overall, I had a very enjoyable stay. I would stay there again. I hate big businessperson hotels. Ravouna 1906 is a authentic as they get.