Service dogs or therapy dogs, I think are fine... then again, I've never seen anyone walk in with a dog before. I would leave the dog in the car first and ask, then bring it out if they say yes... then again, because they mostly sale apparel, I don't think it would be a good idea to bring a dog especially if it sheds a ton.
No, I do not believe they prohibit dogs.
I do not think they have any signage for what you request. Please be mindful that it is a place for clothing and supplies, and there are others people out there who have allergies.
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