I've also read and heard good things about the Empress Zoe. It's very close to the Four Seasons. There's a description here: http://www.turkeytravelplanner.com/go/Istanbul/IstanbulHotels/IstSpecialHotels/EmpressZoe.html Don't know about elevators (important), or the size of the rooms.
Wendy
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Booked: Uniworld Egypt, 2015
Tauck Amsterdam to Budapest, 2016
Paul Gauguin, Societies & Tuamotus 2016
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