Lol yep, Acer is cheap of course the thing is going to fall apart.
If you're going to buy from a Taiwanese company go with ASUS.
Anyways, you'll have to buy a whole new keyboard and install it yourself (cheaper but you could mess up) or by a professional which would cost probably a little more than $100 (price of keyboard and labor)
***** you what? You know, he can just simply but the ****ing button back, it's simple as that.