So I am a newbie to using a bag for edc. I usually carry a knife, light, etc. on my person, but I now I am in need of a messenger bag (no backpacks). I will be using it every day so it needs to be pretty durable. It does not need to be huge, just big enough to fit a water bottle, a few books, and maybe a few other things. I would prefer some sort of water resistance, but it is not necessary. I am on a budget too, so try to keep price to a minimum. Also, it needs to look non-tacticool. Ill be wearing it when I am dressed up. Which brands and models should I look at?