This has been asked for a few times, and I’m not sure we ever had much of an answer on this particular topic.
Personally, I’d love for there to be toggle options on beacon controls to allow people other people to build over and/or under your beacon.
I’ve build an ‘Inn’ for my alts to have rooms in, and it would be awesome if they didn’t have to own the downstairs and roof plots. Then I could just have blank rooms and let anyone plot and own a single room in the building.