I need some help I want to buy my sister a macbook pro but the newer versions are a bit out of my budget. I was looking at this though http://albuquerque.craigslist.org/sys/2724711392.html on Craigslist I wanted to know if $650 is a good price to pay or not? It's a 4 year old computer and the new macbook pro is $1199, so does the pro really retain it's value that much after 4 years? By the way thanks for any help.