A few quick tips. Check your state for their laws about public access rights of emotional support animals. The ADA states emotional support animals do not have public access rights. Only true and trained service dogs (about 18 months to train one to public access standards) have public access rights. In some states, a service dog in training has full or limited public access rights (
State Laws | Service Dog Central) especially if you are his/her trainer.
I am training my daughter's service dog. I would recommend you read the disposition portions of "A Dog Who's Always Welcome" prior to picking your pup. It may help you decide which pup of a litter suits your needs.