Hi Callum
Well, first off, we have no rent-a-mob. Everything happens within a closed studio at CBS Radford (in the Valley). We tend to know who the HGs (houseguests) will be a couple weeks in advance - via the CBS website. Also, they are sequestered in hotels for a bit, and then for a few days together within the BB house before the show and the feeds even start.
The first show airs, then they turn on the feeds - which we pay for... about 15$ per month.