MDU stands for multiple dwelling unit. Basically it means apartments. There are two main rules when installing cable in apartments, and they are: Do not run lines where there is foot traffic, no going in front of doors, or across paths. Do not damage walls. The reason behind both is liability. Once upon a time someone tripped and sued the company, and now we can't run cable more than 10 ft away from a cable jack. Another is damaging walls allows apartments to sue.
These 2 rules create a dilemma. Lots of ghetto apartments have one cable jack only, in the living room. Everyone who moves in wants all 4 rooms hooked up, but can only have the living room installed. I have had entire families of section 8 dwellers screaming at me to hook up the other rooms, and I have to shrug and say sorry.
One time a woman was hysterical. She was on the phone with her auntie yelling how much of a douche I was. As I was hooking up her stuff in the living room, her 3 year old snuck up and tried to pick pocket my wallet.
I finished the install and stepped out. She was still yelling on the phone while walking between the other 4 rooms as I left.
I have to tell the rules to about 2 people a week. I'm not going to endanger my job because you want your kids to have tv's in their rooms. How about you sell the tv's, get rid of cable, and go buy a house with a yard away and some space. Your kids will thank you.