Why does the client need control of your computer? Just out of curiosity. What does the client need to use TeamViewer for?
Edit- my digital literacy is horrible, but I'm aware that there are legitimate reasons to use it.
In any case, if you don't think the client should need to use TeamViewer, tell them so. Don't give them remote access to your computer. It's your choice, not theirs. I would be wary of that sort of thing, too. I don't blame you for being concerned.
