I am in a situation where I am renting a room in a house with four rooms. Two of the other rooms are being rented and the fourth room is occupied by the landlord's son. The landlord's son is incredibly messy in the shared areas such as the kitchen and living room. Many of his messes create mold, and on the lease it is stated that tenants are required to prevent mold, but because he didn't sign a lease, he isn't legally required to. I share a bathroom with him, so any mold he creates in the bathroom is my responsibility. The lease also states that we cannot conduct business in the home, and he has Amway meetings(yeah, I know, he's a moron.) in the living room almost every day, and his inventory fills the house. I cannot access the kitchen because of his messes and the living room is full of his Amway junk. On top of all this, the lease states that they can charge me if the landlord has to clean up any messes when I move out, even if the son made the mess. Does anyone have an ideas on things I can do to improve my situation?
P.S. The lease states that tenants pay for utilities, but on another page it says that landlord is responsible for paying. I'm not if this information could be used.

