traveled on 26th November, 2016 by Eithad Airline via Abu Dhabi...bought online ticket of 68k... hotel cost of 25k for five nights...bought Istanbulkart of 7 turkish lera, you can load balance from any tuck shop by the side of tram stop. 2.25 lira per trip. Donor is the common meal over there from 4 - 10 lira... i suggest to walk as much as you can or eat simple..
Here to reply you any quiery about Istanbul as it was my second visit.