I’m looking for a used MacBook Pro 13” for personal use. I’ve been searching but haven’t really found the answers I’m looking for. What year of computer should I be looking for? I know the newer ones can’t be upgraded with RAM but the older ones can. Also know if it is a retina it can only go up to 8gb but if non retina it can go to 16gb. What I want is 16 gb of Ram and min of 512 gb hard drive so what years do you recommend? Don’t want to upgrade one that’s too old and still be slow due to everything else being outdated.