Spot on.
Just next to Sishane metro station, easy walking distance to the Galati Tower.
Get an Istanbul pass for 6 TL, and enjoy the public transportation system for like 3 TL per ride. I used Uber a couple of times and I worked even though there is some weird stories around it. I just hate Istanbul (or better big city) taxis. Always willing to take a bit extra.
But after all of this city visiting exercise you come home in this amazing place that is just awesome. Not just clean but my bed was made, clean towels each day. Just everything I needed.
Thank you Ece, you have a phenomenal city, and a beautiful place to stay.