We spent a long weekend in Istanbul by http://www.packagetoursturkey.com We had o idea where to visit but this tour company guided us and made our stay very enjoyable.
They communicated well through email prior to our visit, explaining all details and did not require money up front. We paid after the event. They picked us up from the airport and escorted us to the hotel, arranged a private guided tour around the city with and excellent English speaking guide. (his knowledge and English accent were perfect). The company had purchased tickets for the palace in advance which meant we did not have to queue.
In the evening we were collected from our hotel and taken to a boat for an evening dinner cruise with entertainment. A most enjoyable evening.
We were also collected from our hotel in good time for our return trip to the airport.All prices were very reasonable.They are to be recommended.