I agree with Lorraine completely

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Like Lorraine said, there are many, many unexpected costs involved with breeding a dog, especially one as small as a Yorkie and it's very possible that you could lose her in the process. Reputable breeders are lucky if they break even on a litter as all of the expenses really add up.
I have a Maltese/Yorkie X who would have cost me $0, but I gave the rescue a donation as she was an expensive little dog to treat - but she definitely is not "worthless". I adopted her from a rescue I foster for and they get a number of small dogs in...their regular adoption fee is $100 which includes spaying/neutering, all shots, and any other health issues that need to be treated. There are countless dogs being euthanized every single day, including Yorkies...why add to the problem?
By the way, kudos for researching and trying to make a responsible decision

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