In general, I was satisfied with my stay at Sevin's place. For the price you pay, you will get a spacious two bedroom apartment with a large kitchen which serves as a living room as well. The place is located conveniently within a walking distance to the Taksim Square and Taksim Gezi Park (both are less than a mile or ~15-20 minutes of walk). You can also easily access the Istiklal Caddesi (the Independence Boulevard) and visit all the major tourist attractions. Just take into account that finding an apartment might a bit of a challenge since Istanbul streets bend heavily and might want to carefully follow the Google Map to not get astray while walking to apartment. The apartment is in the basement so this is something you should be aware of as there is a bit of humidity there, however it was worth the money I paid.