So you are going to walk into the office day after day wearing the same suit............You only really need one matching outfit that looks good to be well dressed - hat included. Anything after that is a discussion between you and your bank account. One suit. One hat. After all, three suits in the closet and two hats (or twenty) on the rack don't help you look better on the town. One hat will do. Might as well make the hat and suit black so that you don't draw attention to the lack of options in your closet.