A kit as in equipment wise or ingredients wise?
I paid $60 for my starting equipment, it came with everything needed to get started other than the pot so capper, fermenter, hydrometer some tubes, racking cane bottle brush and a book. probably would have been a bit more expensive purchased separately.
As for ingredients, buying in bulk helps a lot but if you are getting stuff for a single beer, i find that ingredient kits are a better deal