I don't currently have this problem but I do want to comment on it. According to US Federal Law, although your board is entitled to ask for supporting materials which document the need for an emotional support animal, federal law does not require the tenant to provide proof of training or certification of the animal. A doctor or therapists letter identifying the need is sufficient "supporting materials". Note that the tenant need not disclose the details of the disability, nor provide a detailed medical history. Nor is it appropriate that an ESA dog wear a service vest; if you had an emotional problem would you want to be "branded" as such? I don't think so. The incident that you refer to of the dog being present in the pool area sounds like a "one-off" and should be treated as such reminding the tenant of the rules and regulations for pets on the premise. For the elevator if a person was severely allergic (or afraid) of dogs, why would they even considering entering an elevator with a dog? To alleviate this type of encounter, you could develop a house rule that makes everyone responsible: if an elevator has a person in it, the dog owner must wait for an empty elevator. Conversely, if an elevator has a dog in it and the person entering has a severe allergy, they need to wait for the next available elevator. Dogs barking, incessantly should be treated as a regular "noise nuisance" complaint.