Personally, I would very nicely inform the trainer that my Yorkie WILL wear a harness, NOT a collar. It might be easier for the trainer to teach his/her BIG dog with a collar/choke chain, but Yorkies are not big dogs. No matter what they (the Yorkies) think!! Yorkies have very tender necks and I for one would not use a collar for training especially in a place like Pet Smart. There are too many distractions for dogs in there. And no matter how well they behave, someone, is going to approach your dog with the "ahhh, isn't he/she cute. Can I pet him/her/" question. I've seen it happen more than once. So good luck. The trainer might be a bit miffed, but who's more important here?? The trainer or your dog?? I think we all know that answer!!
