Even though Shelties have many wonderful qualities that make them great pets, there are a few things to consider when you are looking for a companion. They have two traits that may cause potential issues. They have long hair with a thick undercoat. They do shed but with regular brushing, one or more times a week, you can save on your furniture and also keep them looking their best.
Shelties are also talkers, they like to let you know what it going on. Although they are easy to train, it is usually impossible to keep them from not barking when someone is at the door. They also love to play and will talk to you or their playmate while they are playing. If you really want a Sheltie but live where they just can't be barking, there is always the option or bark collars. I guess the idea of surgical removal of their voice box just seems cruel to me as this is the way they communicate with you.
Lastly, because Shelties were breed to herd, they are very energetic. They are happiest when they have a place to run around, or are able to go on walks with you. They also love to have other dogs, cats, geese or anything they can play with or try to herd. This is not required to own a Sheltie, but will make their life more enjoyable, if it is possible.
If you feel that you can assume the responsibilities of keeping up with this wonderful breed, them a Shetland Sheepdog may be for you. Please contact me if you have any questions about Shelties in general, I would be happy to tell you about my experiences.