Training and intelligence
Dachshunds can be a challenge to train, and do not generally excel at obedience training. Being independent and clever, they have a tendency to want to do things their way. If you don't find the right way to motivate them they may well be stubborn.
Temperament
Dachshunds can be quite independent, in that they tend to like to do things their way. They are playful and affectionate. There are smooth and wire haired strains, with the latter being more out-going, although all are capable of having their own opinions, which they will act on if they feel it necessary.
Attitude towards strange dogs and people
Dachshunds need to be socialised in as many different situations and with as many differnet people and dogs as possible. They will especially need to be socialised with children if they are to have a positive attitude towards them.
Grooming and shedding
Dachshunds have three different coat types - smooth, long and wire haired. Obviously there will be more grooming in terms of brushing with a long hiared, while a smooth haired is easier to maintain. The wire haired coat will probably need attention from a professional groomer in the form of strippnig and trimming.
Exercise
The Dachshund will need exercising - they were bred to hunt, and can have a surprising amount of energy for such a short legged dog. Be careful of their back though, and do not encourage jumping or any activity that might jar the spine unecessarily.
Need for company
Dachshunds tend to bond most closely with one person, and then be their shadow! They do enjoy time with people, although they will tolerate being left for short periods if accustomed to it.
General
These little dogs have a big bark. So long as you take care with their long backs, Dachshunds should have a long life.