well, I asked the redoubtable (and extraordinarily well-liked) Agent Hilda about this. She said that a one hour show would cost £40k and a half hour show would cost £22.5k. And, being the MD of a multi-national telly company producing shows for every a wide variety of channels from BBC1 to MTV and HGTV, and having seen over a 2000 programmes go on UK terrestrial TV, she'd probably know what she's on about,
Crankers is right about getting the content right (although I still think there's stuff in this show that is right), but if you want people to watch stuff on telly it's got to be neatly put together, and the people who do the putting together aren't cheap.