Just bought a macbook pro refurbished. The thing is, there are files from the previous user on this computer. There were pdfs of math homework for example. Is that common in refurbished models? I thought the apple technicians install a fresh copy of osx. anyway, there's also apparently 800mb of pictures and 1gig of music that I can't find according to the disk utility. where are these files? Maybe I should reinstall a fresh copy of osx. The refurbished macbook doesn't come with a usb installer for mavericks though. Where do you buy them? I couldn't find any at the online store. I'm such a newb. thanks in advance for helping me.