Chihuahuas are yappy, highly-strung dogs.
FALSE! Chihuahuas can actually be VERY quiet, well-behaved dogs. It just requires the proper amount of training and socialization, as with ANY dog. If left alone for long periods of time, they will become bored and reactive to what’s going on in their surroundings. They can also be nervous in social situations, as they can be very wary of strangers and take their time in getting to know other people. This is probably why they have a reputation of being yappy or highly-strung. HOWEVER, they are not highly strung with their family at all. If they are properly taken care of, kept indoors, and well socialized, they are one of the most loving and loyal dogs.

Chihuahuas are outdoor dogs.
FALSE! Chihuahuas are very sensitive to the cold and they crave human love and attention. They are NOT an outside dog and MUST live INSIDE the home.

Chihuahuas are sensitive to the cold.
True. Owners must be very sensitive to the fact that short-haired Chihuahuas, and even long-haired ones, are vulnerable to the cold. In temperatures of 35-40 degrees Farenheit, it is recommended to dress your Chihuahua in a special dog sweater for brief walks (believe it or not – they will thank you!!). Walking your Chihuahua in temperatures below 35 degrees Farenheit is strongly discouraged, especially when there is a wind-chill factor. In some cold regions, an indoor heater will be necessary to keep your Chi comfortable.

Chihuahuas don’t need socialization.
FALSE!!! Socialization is the act of introducing your Chihuahua to a wide range of situations so that he is comfortable in them. Dogs need to be socialized from a very early age - especially Chihuahuas. The personality of your Chihuahua will be strongly affected by his interactions or lack of interactions with people, situations, and other dogs when he is a puppy. By socializing your Chihuahua puppy you make him familiar and comfortable with a range of situations so that he does not become fearful of these situations when he grows older - which can result in a range of behavior problems. Socializing is especially important from the time when your puppy is born up until he is 12 weeks old. He needs to be with his mother and litter for at least the first 8 weeks of his life. When you bring your puppy home you should give him a lot of love and attention and introduce him to other dogs, neighbors, friends, sounds, and so forth AS MUCH AS POSSIBLE. You should do this in a very non-threatening way so that he feels secure but so that he can see that these things are going to be a part of his life. Socializing your puppy will help him to grow up with a sound temperament.

Chihuahuas are not good with children.
FALSE! If you properly socialize your Chihuahua from a very young age, and ensure that you acquire a Chihuahua with sound temperament, they are very gentle and loving with children. However, if a rough child unintentionally harms him he may retaliate in defense. After all, would you let someone keep poking you in the eye or pulling your ear without doing anything? So young children should be supervised at all times and children should be trained to be extra careful and gentle. This goes with ANY dog though.

Chihuahuas don’t need exercise.
FALSE! Because Chihuahuas are so tiny they can get most of their daily exercise requirement by walking and running around inside and in the backyard. But taking him for a walk a couple of times per week, or even every day, is recommended to keep him extra fit and healthy. He will enjoy it too!

Chihuahuas are not social dogs.
FALSE! Without adequate socialization, Chihuahuas can be very wary and cautious of people and dogs they don't know. They may bark, growl, or stay at a distance until they feel comfortable. HOWEVER, if you properly socialize your dog (like with any dog), they will actually crave and enjoy the company of other animals and people. Many well-socialized Chihuahuas thrive in multi-dog households and enjoy outings at dog parks or dog daycare centers.

Chihuahuas cannot be around large dogs.
FALSE! A properly socialized Chihuahua can handle himself well around dogs of ANY size. They know when to move out of the way if a big dog runs by and how to act if a big dog greets them. Of course you have to be careful around dogs with higher prey-drives, but generally Chihuahuas can be around and even live pleasantly with dogs of all breeds and sizes.

Chihuahuas cannot be trained.
FALSE! Yes, you can train your Chihuahua to obey just about any command or perform tricks. (Look how well-trained the Chihuahuas in Beverly Hills Chihuahuas were!) However, they are not one of the easiest to train breeds. This means you will have to spend more time with them and have more patience while training them.

Chihuahuas shiver.
True. A common character trait of Chihuahuas is that they shiver. However, this characteristic is a result of having a high metabolism, and Chihuahuas usually only shiver when they are overly excited, frightened, uncertain, or cold.

Chihuahuas make good watch dogs.
True. Chihuahuas are very alert and because they can be wary of strangers (if not socialized properly) they love to bark at them - especially anyone who enters their turf.

Chihuahuas can live a long time.
True. Chihuahuas can live anywhere from 11-18 years!

Chihuahuas are expensive to acquire.
Depends. If you buy from a responsible breeder, you will pay $700 or more. If you buy from an irresponsible breeder you may pay only $100, but chances are the dog will have serious medical issues. If you buy from your local animal shelter or rescue group, the dog will already be spayed/neutered, up to date on shots, (usually) microchipped, for only around $120-250!

Chihuahuas don’t shed.
FALSE! Chihuahuas are not one of the highest shedding breeds, but they are not one of the lowest shedding breeds either, they're a medium shedding breed. You will find hair around the home. Chihuahua shed year round, but will shed more heavily once in spring and once in autumn. During these times of more heavy shedding you can step up grooming to reduce the amount hair shed around the home.

Some people claim that Chihuahuas don't affect their allergies, but no scientific evidence exists proving this. Usually people with allergies are allergic to the dander (dry skin flakes) and hair which falls of a dog. Chihuahuas are medium shedders, so if you an allergic reaction to these allergens then you might be better off with a very low shedding breed, such as a toy poodle. If you have your heart set on a Chihuahua, but you have allergies, then the best thing to do is to spend some time around Chihuahuas before acquiring one. Chihuahua breeders or most shelters and rescues will be all too happy to let you spend some time some of their dogs so you can tell whether they give you an allergic reaction.

Chihuahuas love to burrow.
True. Chihuahuas love to burrow under the blankets. Make sure you always keep a warm blanket in his bed so that he can crawl under to feel safe, warm, and comfortable.

Chihuahuas love sun-tanning.
True. Chihuahuas love basking in the sun, the more sun they can get the happier they seem to be. Unfortunately, they are not sensible in this regard and will stay in the sun even when panting begins. Watch your Chihuahua in hot weather to be sure that they don't suffer from heat stroke.

You can choose to have an intelligent, loving dog with an excellent temperament that can do anything you train it to. On the other hand you can have a badly trained, unhappy, snappy dog that no one really likes. The choice is entirely yours.
DON’T BLAME THE BREED – BLAME THE TRAINING!

http://www.chihuahuapuppiesguide.com/chihuahua-faq.html
http://www.k9web.com/dog-faqs/breeds/chihuahuas.html