Can do with some tightening, Decent work
I like the opening line of your book, except the first chapter goes on for too long inside the mind of the protagonist. I literally skimmed over it. Consider breaking it with dialogues? The description goes on for too long. The vocabulary used is vivid, but language can do with some tightening, at times I can smell a cliché. there are places where I like the flow of words. Istanbul is well described, but sometimes the description is way too much, even while describing the protagonist’s state of mind… try using stream of consciousness rather than plain vanilla description which gets too obvious at places. Make every word count, if the word is adding no value, chop it off… often it takes many rounds of editing to see one’s text differently. Sometimes, it also takes many pairs of eyes to spot excess words. I am not sure of the word count of your book, but consider tightening it if it is exceeding 80,000 words otherwise it gets difficult to hold reader’s interest. This is completely my point of view, and am sure different people would think differently.
Read the story now