Crates only have to be big enough for the dog/puppy to be able to turn aroudn and lay down. They don't need to be large. However, Why not give them extra room by buying a big one. Then if you ever need to use it once they are older and larger, ou won't have to go buy a bigger crate. I prefer the collapsing kind that can basically fold up when you are done. We have one for our Golden Retriever and it's really huge. But the front and back flip down into the crate and then rest collapse on top of it and we just stick i in the garage when not using it.