I have two dachshunds. I love them to death but would never get another. They are very loving an loyal, but only with us. With everyone else they are territorial and barky. Every sound or movement outside of our house results in barking.They are extremely keyed up initially when someone walks in the door even when we are letting them in. They will calm after a while, but then if the person gets up to use the restroom or something, they will start barking all over again like it is a new intruder. About the only people they are better with are those individuals who are frequent visitors.
Dachshunds are notoriously nippy around small children and the problem with it is that most children find them cute so immediately bend down to pet them and get face to face. Also they are usually a bump in homeowners insurance premiums if the carrier knows about their presence because of their reputations. My daughter works for a vet and doesn't have a whole lot better to speak of them. The back issues are just another possible problem but we have yet to experience anything with that. Sorry if that is discouraging but it is my experience.