Willing to move to Istanbul so bad!

If you have work in your country.dont give up,just take vacations and come to Istanbul to search work .Istanbul b cause little bit more opportunities to find something.but salary will be low ,even you speak English and Russian no mining you will find good job here cos if you don't know Turkish fluently they will not except, or with low salary as I said above.so if you have good incomes in your country do not cut that tree where you sit safer.good luck

Is 400 usd/month good to cover rent (room in a shared flat) and monthly expenses?

I don't know maybe a bit more would be fine

Thanks! I will definitely try! 

If you will stay with friends to sare payment maby,but don't think sooo

If you have 2 languages then you can work at   the well known private colleges in istanbul as an EFL tutor . By this way U can earn 700$ min . And this is a good standard for normal living  in istanbul. And you will also have a  qualified environment .

If you speak English then your best bet is to teach English. A private K-12 school is the best option and will provide work permits. You can easily find a job that pays 5000 lira, if you a native or native like.