As soon as you've got these preliminary things finished, please, please call us and let us know that you've got him and all is well. We've never had a problem with shipping...none of our pups have ever arrived in any condition other than perfectly fine...but we love them, and we do wait to hear from our new owners on shipping day. It's important to us to know that you have your puppy and all is well.
If you have a long trip home, you'll want to stop a few times to allow your puppy to potty and possibly get a drink of water. Some of these guys are beginning to crate train when we send them home, so they may not potty in their crates. And they're small enough that they may still need to potty several times a day.
Once you get your puppy home and get settled in, just have a good time and enjoy him. Just a note: A little diarrhea is normal after a puppy goes to a new home. It is usually a result of stress and changing environments does stress them a bit. It should clear up in a few days.