Chris Blackburn (ex BBAU producer) recently did an hour-long podcast interview with Ben Norris where he discusses the process of editing Big Brother with a 24-hour turnaround as opposed to editing a pre-recorded show with plenty of time to spare. He has not watched Seven’s iteration so the latter comparison isn’t necessarily regarding BB specifically, but it was quite interesting nonetheless.Would be interesting though to see how long the post-production phase is. We don't know how much is edited together whilst they're still filming, or whether the luxury of time means they end up spending at least twice as long putting together each days worth of footage and as often is the case, over produce the whole thing. With reality series especially they can still be editing episodes as the series airs, even if the footage is months old. Therefore a 24-hour turnaround for a live series can actually be something which cuts out unnecessary wastage, and therefore costs.
I suspect to there are far more than 60-80 people involved - even the most basic one off half hour show can have that sort of number involved, never mind a two month reality shoot.