Hi! This is my laptop: Model Name:MacBook Pro Model Identifier:MacBookPro12,1 Processor Name:Intel Core i5 Processor Speed:2,7 GHz Number of Processors:1 Total Number of Cores:2 L2 Cache (per Core):256 KB L3 Cache:3 MB Memory:8 GB Lately, I've realized 8GBs of RAM is getting pushed to far between Parallels and other apps. Is it expensive to upgrade the RAM (I'm thinking of doing it myself if you don't say the contrary)? How much could I fit and what/where should I buy? Thanks!