I have never used any pack animals, but Goatpacking has caught my attention, they can carry about as much weight as a man and don't appear to have as much attitude as mules, horses and llamas. and you could haul them in a modified utility trailer. if you have a large yard, you can raise them anywhere.
My wife told me no, otherwise I might try this.
check out this video http://www.youtube.com/watch?v=eCFvUt0XZso