I would have thought a communal dish would be cheaper as well as more sightly. Added advantage you can discuss with othet tennants and get to know each other.
Surely free view , which does not require any exterior aerial in SE 23 is ideal.
The new rules seem to instruct not at front of the building. So guess a lot are having to come down. Who is going to enforce.
I do agree that Dartmouth Rd ( lower end ) as a conversation area is rather like shutting the stable door after the horse has bolted.