If you are certain that it's just a matter of a missing screw/screws, then instead of bringing the computer in, get a replacement for the screw/s. Otherwise, their repair center has very knowledgeable people that you could consult with, before you bring the computer in.
I believe they can do repairs. It might depend on what your issue is. I would go there and see what they can do as far as putting the screw/s in or if it's something you can do yourself as a very easy fix, more so if the screw/s are for the outside of the computer. The store may have the right size screw for you to screw in yourself. Ask them and they'll be able to help you. Be sure you have your computer with you so you can get the right size screw. Or you could ask the manufacture of your computer to see if they can give you a replacement screw or depending have it sent to them if your still on the warranty.
Yes they provide upgrades and repairs. It depends on what the issue. Thay are quite good.
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