We stayed at Önder's place for 2 months and it served us very well during that time! Önder and Olcay were very hospitable hosts. The location is great and very accessible to supermarket/cafes/restaurants/metro/marmaray/ferry, although nearby parking is a bit tricky to find if you need it. The central location is great in terms of options for ordering in too.
The space has a working desk and dining table which also served us well when we both needed to work remotely (internet speed is also fast). The apartment itself, being on the lower ground floor, is VERY cool in summer - we almost didn't realise how hot it was until we had to go outside. The downside is that the air can get a bit stale at times, but opening the floor-to-ceiling glass doors to the garden helps alleviate that somewhat.
Lastly, the garden is home to a community of neighbourhood cats - they are a joy to have around (if you're partial to cats).