My Wife and I have two Dachshunds and our Daughter has two. So when we are 'babysitting' her's....we have four in the house. They are a hoot.
You don't want a 'doggie door' with Dachshunds though. They will bring all kinds of 'catches' back into the house. Squirrels, Gophers, Possum, baby rabbits, etc...
Thank God...we don't have any badgers where we live.