Please help with advice (Istanbul)

If I want to teach English or Russian, how much do you think should I charge?

I used to teach Russian in UK around 10 years ago
And I used to teach English in Kazakhstan around a year ago

Now I am learning Turkish myself and have some spare time, obviously don't mind to earn extra cash also I love teaching, I have my own online training school, and maybe with this effort I can even help people to improve their Russian or English, change their lives, help to relocate if needed, teach conversational language more then grammar, as that is all my experience.

I can also help to prepare for business negotiations, interviews etc. Ive been a Career Coach in London for few years so I might help with interview preparation.

But...don't know whats the miminum and max per hour charge that teachers earn here, please advise, maybe you've done it yourself, you've attended such private type of classes etc.

I would appreaciate any advice :)