Very good tour and travel agency
Based on their very positive tripadvisor reviews, we booked a 3-day Istanbul old city tour
I found the service and response of this travel agency to be excellent. Easily 5-stars. My emails were promptly responded to, and everyone showed up when they were supposed to.
The only reason I'm not giving this travel agency 5-stars is because our tour of Istanbul old city was very good, but not over-the-top fantastic, so there is room for improvement (or, for travellers, some reason to consider other options). While a nice tour, we found the English of our private guide to only be good, not excellent (I could only understand about 85 to 90% of what he said), and the tour was somewhat "standard." Like we had lunch in your typical, not very good tourist trap restaurant near the ruins. He did take us a little "off the beaten path" at the sites, however, so it was a very enjoyable tour. Both the guide and driver were friendly and courteous, and they constantly plied us with free bottled water (and you're going to need that, even in the "cooler" winter months). The 5 am sunrise at Istanbul is a bit ridiculous these days (my favorite shots are of the bugs and hundreds of other tourists snapping photos), but I'd do it again "for the experience."
Excellent Tour Operator
Our experience (three families with a total of 8 kids) in Istanbul was super, due to the help of Mr. Sebahattin from Istanbul travel Turkey . Flexible, helpful, always kind and open to the clients' needs, he was precious to us, thank you.