Right now Istanbul is struggling for tourists, hotel occupancy is way down and as a result some hotel prices are the lowest they've been for years. Unfortunately some still go by Turkonomics and try to balance the books by increasing prices!
You'll find that most hotels will give you a discount for paying cash and if staying more than three or four nights provide free airport transfers.
The Nena is right in the heart of Sultanahmet, couple of minutes walk from a tram stop - and in walking distance for all the main tourist sites in that area, definitely a good location for a first time visit.
JF