Cheap pc to run minecraft and tf2?

Probbaly 500-550 i will also need a monitor unless any monitor will work with it or is a laptop with a USB mouse be better i'm just worried that the laptop charging plug in spot will break if my little sister uses it

I don't know about PC and stuff, so this might be useless, sorry. But you can get the pocket edition of Minecraft free if you go to http://featu.re/BGGMYK referral code: BGGMYK