If i want to visit a friend in China from Ukraine,to get a an L-type visa what are precise requirements?

I' m a foreign student in Ukraine; want to visit a friend in PRC. I want to apply for L-type. I have all the documents I was told to submit from this page but when I had to apply for it, I was asked to have at least 3000hryvna on my account for medical insurance. It is compulsory? And how long does it take to have mine after the day of application.