An organizational chart is because you can had facts and other information that are based on it. You can also had a map and maybe some pictures or if your a good drawer you can draw a sketch. I may be wrong this is just what I would do.
Answer: Your roomate and you would normally pay the same amount as the other. So the rent would be divided evenly. Although, sometimes it can be split more than evenly if one person is willing to pay for more.
