Mehmet's place was great, just as described. We did not meet Mehmet himself, but he arranged our transport from the airport and Mehmet's brother met us and showed us the place, and gave us an overview of what to see in Istanbul. He met us with our ride back to the airport as well.
The place is at the end of a quiet street, but there are lots of upscale hotels nearby. Restaurants are down the street, and a really neat market street, and the major tourist areas are just a few minutes walk.
The only warning someone might need, is that there are cats that want to come to the back door and will come inside if you don't shoo them away. This was not a problem for us, but if you don' t like cats or are allergic to them you might not be able to enjoy the back courtyard.