I'm certainly not a pro but I have done my fair share of painting over that last few years. I use Sherwin Williams and it covers beautifully with two coats, tried other brands first but was not happy. Their Duration paint is expensive but does wash well. Just make sure that you don't roll so much that you take the paint back off the wall (I've seen this...shhh...my husband used a gallon and a half on our tiny bedroom, he had to use 3 coats because he would roll and roll and roll...now I do all of the painting)
Also...I have found that no matter what color I am trying to cover, priming the walls first really helps get a nice even finish.
Good luck!