i've had two yorkies. it was a few years back. they are great little dogs. they are one of the hardest breeds to housebreak. they can be anywhere between 3-7 lbs. although my first yorkie was 13 lbs as an adult! he wasn't fat, just a HUGE yorkie.

bringing a new yorkie into the household with another dog can work. but it's really up to both dogs. some yorkies can be dog aggresive. it's the terrier in them. fortinatly mine were great with other dogs. they were thouroghly soceilized. if you want a puppy you may not have any problems, but if you are going to adopt an adult, you definatly want to introduce the two dogs on neutral grounds like a dog park or a neighbor's fenced yard.