Istanbul: we did on our own. The cab drivers did try to push a tour, but stand firm and just say where you want to go. Everything is pretty much within walking distance of the Blue Mosque. We did get turned around at one point and had to take a cab to the Grand Bazaar. In the Bazaar, make sure you haggle and walk away if you don’t like the price. They don’t care if you have Euro, Lira, or US$. From the Bazaar we just took the tram back near the docks and walked about 4-5 blocks back to the boat. (There is a Starbucks about 3 blocks from the docks) The Turks are very pushy and want to bargain EVERYTHING. Stick to your guns and just walk away if you don't want to pay. If someone keeps coming up to you just say No Thanks and keep walking.