We stayed in Meric's apartment for 2 months and it was an excellent experience! Meric received us and even bought some food for breakfast since we arrived late at night. He also gave us some useful tips about the city.
The apartment is really great, cozy and very well located. It's just a few blocks away from one of the most turistic areas of the city and at the same time, located in a very, very quiet street. If you go up a few blocks you reach Taksim square, where you can take the subway that will take you to all parts of the city. But you can also reach many landmarks on foot. Istiklal is about a 5-minute walk and if you enjoy walking, you can certainly go to the Galata Tower, Dolmabahçe Palace, Galata Port and other turistic areas on foot (we did this several times). You are also very close to one of the ferryboat stations that will take you to Istambul islands.
It's very easy to buy groceries. If you go down the street for just 2 blocks you will find 4 small markets that sell fresh fruit, vegetables and basic things for your day-to-day groceries.
About the apartment: the kitchen has a small stove, an electric oven, a good fridge, freezer and all the utensils that you may need for a long stay. We worked from home and there's a nice space to work with fast and stable internet. The bed is really comfortable.
We can't say enough about how much we enjoyed our stay at this place and I'm pretty sure you will have a great time just like we did. Mind you that Cihangir / Beyoglu is full of stairs and going up and down the streets, but I guess that's the charm of the neighborhood and that's what makes it special.