I think you have found sufficient evidence to steer clear from the breeder. If you are not 100% comfortable why not take your time to find a breeder who you know is reputable and does not have 24 dogs. I didn't look at the website but from the information you provided it does not seem like a place I would want to buy my dog from. Why not try a breeder in your area that is on the YTCA list and shows and breeds one type of dog.
Yorkshire Terrier Club of America