I adopted Scuffy (fostered under the name of Tanner) a couple months ago. I had been looking for a breed that worked fo people with allergies, and found that a Yorkie also met other criteria I was looking for (small, etc.). Tanner/Scruffy had been offered for about 3 months before I began the adoption process. He was listed as a Yorkie mix, which he is, and about 5 years old. This was good because I was looking for a mature adult dog. He was also said to be "housebroken". After I had Scruffy for a week, I took him to the vet for a check-up. Imagine my surprise when the vet told me that Scruffy is no more than 2 years old! That explains why he chews everything in sight. Scruffy is also NOT housebroken, but is getting better.
Before you adopt, be sure you ask everything about the dog and then cross your fingers that what you're told is the truth.
If he wasn't so sweet sometimes, I'd have to give him back!