Just letting you know, the FCC prohibits landlords from disallowing satellite dishes and broadcast antennas from being installed in areas controlled by the tenant. You can disallow them in common areas (like the roof, which you mentioned), sure, but the FCC will come down on you hard if they get wind of you trying to interfere with them installing a satellite dish on their balcony.
I'm in Canada and we've declined people from attaching anything to their balcony's railing. If they want to put a dish on the balcony, it has to be on a stand. My upstairs neighbour has one like this.
We've done this rule about attaching things to the building/railing because the building is actually two buildings one is a heritage building so nothing is allowed to be attached without prior approval of the heritage committee of the city. Since that building can't do it, we made the decision to do it for the new building.
We had to get permission to use a new type of metal shingle that looks like a traditional shingle but it has a 50 year warranty. Since that roof can only be serviced by one company in town (it has a steep roof like a church so only that company is actually able to do it) we wanted it done once and not have to worry about it. Even the method we used to clean the outside of the building had to be approved.
Exterior walls are common areas owned by the landlord:
"OTARD rules do not apply to common areas that are owned by a landlord, a community association or jointly by condominium owners. These common areas may include the roof or exterior walls of a multiple dwelling unit."
