I really enjoyed my stay in this small but very nice hotel.
The rooms are modern and clean, have everything you need, even a huge TV, a desk, a small fridge, nice bathroom with shower (lots of water coming down).
The stuff is very friendly and helpful (explaining how to go to Istanbul, calling taxi, ordering pizza on Sunday evening, etc.).
The breakfast buffet has everything you could imagine, from cereals, fruits, vegetables, cheese, eggs, sausage, bakeries, etc.
The attached restaurant is small, but I liked the taste of the dishes they prepared for me (although I like the meet a bit more crispy, but that is my personal favor and I did not tell them about that).
There is a big bazaar just 200 meters from the hotel (on Saturdays) and I really enjoyed it (was walking around there for more than one hour and still haven't seen everything).
If you want to go to the Istanbul city center take a taxi from the hotel to Kartal Metro (about 15~20 Turkish Lira)
From there go to last station Kadiköy (for only 3 TL), then take a ferry to Eminönu (3 TL) and either take a walk or go with the tramway to the Hagia Sophia or Sultans Palace
The hotel is maybe 10~15 minutes from Sabiha Gokcen airpot with a taxi and the cost for the drive is about 30 TL
The water drain in the shower was not able to take all that heaps of water that is coming out of that nice shower in the same time, so I had to be careful to not produce a flooding in the bathroom, but wouldn't have been a problem, as the bathroom floor is tiled too.
The hotel is a bit far away from Istanbul city center, but with taxi and Metro it takes you at max 1 hour and you are there.
The restaurant was closed on Sunday evening, which I didn't know, but the hotel stuff ordered a pizza for me, so I didn't have to starve.