For that price you will get a bare bones unit which is good enough for what you want to do. To give you an idea, my wife is still using my old laptop and it has to be 10-12 years old. The only other suggestions I have is to avoid the ones with the 10" monitor screen unless that is what you really want. The screen and keyboard on them are just too small. Sometimes unusual places like Staples has very good prices on computers as well as Best Buy.

I have had the same idea as you except I am thinking of getting a tablet computer to take to the convention. I just don't want to spend a lot of money on one so I am trying to find an off brand color screen e-reader that I can download my scans to.