I’m thinking about taking my new yorkie puppy to a training class, probably at a PetSmart. Has anyone been through it? Did it actually work? My puppy is 13 weeks old. He’s very smart. Potty training is a little weird, but I’ve trained him to do somethings already like getting in his box and not running outside everytime the door is opened. Also, how long should I wait until I enroll him in a class?