$450 is really a reasonable price for patella surgery. If it makes you feel better, my darling Gracie (RIP) had both knees done and she was as good as new in no time! As for her breath, did the vet suggest a dental cleaning? This is important in Yorkies so you might ask him about it when she is more used to being with you. I wouldn't traumatize her with anything for a while. I was suspecting this breeder might have a reason for giving her away. Good luck with your new little girl!! Aren't they awesome???