We stayed at Mehmet's place in December 2015. We stayed for 2 nights and it suited our needs perfectly as it was set up like an apartment complex and was central to the old town of Istanbul. We didn't come with bags so it made it easy to walk up and down the steep street near the house. Bear this in mind if you have luggage, and I would recommend a taxi to the place if this is the case or you are elderly and don't like walking up hills!
Apartment was super cheap and modern, although some things were falling off i.e. Light switches, handles, etc but you get that everywhere. Would have been good if we had tea/coffee and rolls of toilet paper. You can check in and out at any time and the free wifi worked very well.
Thanks for having us!