My Macbook Pro purchsed in 2011 has only about 25 GB of storage left so I need to either increase the storage or replace the hard drive. I'd kinda rather keep the hard drive it has so I can access all of my files and not have to move them back into the new hard drive. How do I go about this? Can I add to the memory (which is currently 500 GB) or do I have to replace with a 1 TB or larger? Where do I get the hard drive and what brand should I purchase?