Great little place a few mins walk from Istiklal and a one min stroll from tophane tram station. The place is perfect for solo travelers , especially first time visitors since all public transport and the main shopping street are within comfortable walking distance. There are great cafes to the front and side of the apartment building (if you love Lebanese food do check out arada cafe, it's right next door). Cihangir, the cool neighborhood with the bars and shops and art exhibits is nearby too (7-10min on foot).
Kaan (the co-host) is a great communicatior and made check in and check out super easy. The place was clean and had all the basics sorted (appliances , toiletries, cutlery, etc). There's hot water 24/7. The area is safe and clean and full of locals and tourists so you don't feel uncomfortable walking back late at night. There's a mobile shop right below, a pharmacy across the road, and a general store to the right of the building. There are cool vintage stores scattered all across the side streets leading to the building. Although central, the street is quiet at night so you can sleep peacefully.
If you're landing at SAW, take the havabus to abdulhak hamit cadessi-taksim yonu (52.5liras, you pay in the bus) and from there take a taxi to the apartment (30 liras). This is the only money I spent on a taxi my whole time there. Take the metro/tram to everywhere else.
Highly recommend this place for those wanting a budget accomodation but a central location.