I like my puppies (ones I sell and keep) to have the dog to dog experience that's needed (IMO), and that happens at a young age. If you take the puppy away at 7 weeks, that's a week of experience (from learning, to socialization, to corrections) of dog to dog (mother to puppy, puppy to puppy, or puppy to other dogs in the household) that I think is almost required to have a healthy personality. At around 7 weeks, the puppy is really learning to be independent, which I think is helped by seeing the other puppies act that same way.
With my puppies, they start to sleep alone in crates at 7 weeks (at night, with a piddle pad in the front and a blanket with a toy and a small towel in the back). After about 3 days, they don't wet in their crate at all, so by the time they're ready to go to their new homes, they're already crate trained and sleeping all night (about 6 to 8 hours) without messing.
My husband and I went to the local pet store and bought over $200 worth of "stuff" for Ellie. I talk about her alllllllll the time. Someone's gunna hurt me sometime soon I am sure. 