Hello Jessi,
We have a solution for your need : The NHC Media for Skyboxes. The NHC Media Center works for Skyboxes, Apartments and Houses, even they are sharing the same parcel because it does not use the media URL of the parcel and it does not use "shared media" too, working for all Webkit Viewers.
Unlike all the others systems in its categorie, it does not require a new viewer to play videos because it does not require the "shared media". The system sends the command media directly in private mode to all residents inside its range and the range is adjustable using the receiver's menu. It does not use shared media, it does not the media URL of the land.
The media system works for all Webkit Viewers like Phoenix, Imprudence, Singularity, etc, a newest viewer like Firestorm or SL v3 is not required.
If you want a solution that will work for all, this is your best option.
Prims required for each unit : 5 Prims.
For better information or demo, contact in-World.
Obs.: Do not buy the default system in marketplace, because they are for parcels
Regards;
Sylvio Runo