I have a puppy mill rescue, not a yorkie but a maltese/poodle mix. He now lives with my Mom. We never had any health problems with him. You never know in the long run though. If he is healthy now and you have a big enough heart to adopt him..go for it! You could get a very healthy puppy from a good breeder and down the road it could have major problems. Would love to see a pic of him if you get him