1. if there is any body live in 67/F better tower 23 room EDF or G just put a big poster on the windows (inside the apartment) for 1 to 2 month I think it is easy to be pay attention by another people.
2. I still think put the paper in the letter box will not have some problem. Many decoration company do the same never have complain. I can try to do this in tower 2 (I will make the paper in black and white since it can be faster by using copy machine.)
I think if it is just easy to contact to all RC owner by this web is very convience for us gathering power.