i am quiet the linguistics person..
speak english, serbian, spanish..
I also understand Latin 1

and now going to take Mandarin online for summer :)

I want to be fluent, so i want to know what approximation i can expect.

Well, if you work at it for the whole Summer and find some Chinese people to chat with you online to practice, you could probably learn a good basic vocabulary for written communication.

As for pronunciation though, without a teacher or tutor to properly train you, that would be very difficult.

To become fluent, expect years of work since with Chinese, you basically have to memorise each character one by one; it is doable, and since you already have a few languages going, your brain is already in gear for more language-learning.

To truly become fluent, the best way would be actually studying in China so that you could immerse yourself in the language and its culture (which is important to learn their way of thinking when it comes to how they speak).

Best of luck, and I hope you enjoy learning Mandarin (I sure do)!

it's not easy, especially you know mutil-ligual. i know english and two dialect in chinese. and it's still hard for me to learn manderin. it's take at least months to a year to learn just basic conversation. years to became more advance. but fluently, never going to happen because there are slangs words in manderin just like any another language so you can't be that fluent even if you studied hard.