Our guide Sercan met us at our hotel on time, as arranged.  The car was large and clean, the driver was very professional.  We discussed what we wanted to see and he also made some very good suggestions.  He was very knowledgeable and answered all our questions.  We were able to see places we would not have thought about.  We had different age ranges in our party and Sercan was very accomodating, going at our pace, we did not feel rushed and he was happy to take breaks when we needed.  We had the most interesting day and saw a different side to Istanbul.  Sercan was such a lovely person,   I would highly recommend this tour and agency.