This apartment is situated in a perfect place for anyone interested in visiting all Istanbul's main attractions. My family and I reached all the main attractions including the Blue Mosque, Topkapi Palace, Hagia Sophia, Grand Bazaar and the seaside by foot only. We also visited Dolmabahce Palace in Karakoy which was very quick and easy to reach via tram. If you're visiting Istanbul, definitely visit Dolmabahce Palace - it's amazing and definitely worth 40 lira.
Yavuz's apartment was exactly the way the pictures showed - nothing more, nothing less, so be assured that you are booking exactly what you see. Just one thing about the location of the apartment that you may want to know, though, the area is very hilly - you have to walk a distance uphill until you get to levelled ground, which, for some people, may be tiring (i.e. elderly/overweight people).
Bayram (Yavuz's brother) was very helpful and straightforward in his hosting of our stay. He gave us tips and told us about good places to visit and the directions to them. Bayram was always readily available on WhatsApp whenever we needed something. He seems to be a very organised person. Bayram also helped us with arranging a taxi to take us back to the airport at the end of our stay.
One thing I noticed about the area is that males were the predominant gender you would see around. This wasn't a big issue, though, as they were all respectful and simply getting on with their everyday lives.
Around the area, there are a lot of shops (and bakeries) whose locations are helpful for whenever you need to buy something quickly (e.g. milk, etc). There is also a supermarket (Sok) close by, too.
All in all, a good apartment and a good host. Would stay here again.