I would like to add a few points from the point of view of someone, who has lived in Istanbul for several months as a single foreign female:
- In general I'd say that Istanbul is a rather safe city, however the area Tarlabaşı, where Serai was living, has an awful reputation. Some years ago (so I have been told by locals) it was a complete no-go-area, eve during the day. It is still known to be an area where a lot of prostitution, drug trafficking, burglaries and violent crime takes place. For some years now there has been a regeneration project going on there, as a result of which many of the buildings are now completely empty. I'd assume that that makes the area even more dangerous. I have been to Tarlabaşı a few times during the day but I would not recommend that any single female traveller went to stay there, particularly in a basement flat, which are quite easy to break into.
- Secondly, a single female traveller in Istanbul is likely to be constantly approached by local guys in the streets, especially in touristy areas, such as Sultan Ahmet or the Galata Bridge area. It is quite usual for such guys, for example, to offer to show you "the best place to take photos of the Blue Mosque" etc. Such guys, I would say, are not very respectable people (it's not ok in the Turkish culture for a man to approach women in the streets) and I don't think it's a very good idea to get too friendly with such people. Given the fact that Serai was visiting Turkey for the first time she may not have been aware of such "rules". I'm not saying that all such guys are criminals but I would guess that most of them are looking for ways to take advantage of naive travellers somehow.
- In my experience, young people in Istanbul tend to be very experimental with drugs, much more so than Europeans. I would also say that there's much less awareness there of the dangers of, say, hallucinogenic drugs, than in Europe. Taking them seems to be considered pretty normal, for example, among students
- Finally, there is quite a bit of organised, underground crime in Istanbul, given the city's location between Asia and Europe. This includes, among other things, international drug trade and human trafficking. But I guess one would have to be very unlucky to get mixed up with something like that.
Anyway, I hope Serai will be found soon and that everything is OK with her.