I am looking at replacing my Mac mini 2012 i5 model with a MacBook Pro 13" i7 or 15" i7 at the end of the year. It is the $699 base model, with the 2.5GHz Core i5, 4GB of RAM, and a 500GB HDD. There are no marks on it (Except for the removable bottom plate.) There is all of the original cables, the original box, and the receipt. How much do these Macs sell for, and what can I do to put the value up?