File transfer security



it's my first time using Teamviewer free version to allow support from an external software company on my pc, as a private user.

I'm quite worried about security of the files that are stored on my hard disk and I would like to understand how the file transfer functionality works.

In particular I would like to understand if I'm able to monitor or if I'm able to evaluate any kind of request related to file transfer in/out bound from my hard disk.