I currently have a dog with separation anxiety, and a neighbour that has called the council because a tail wagged too loud and thumped on the floor. I've also had a previous dog that had epilepsy and a heart condition. I had an arrangement with another neighbour that our dogs could have 'playdates' when needed. They all got along great, and his dog would be sent over for a visit, or mine could go over to his for a few hours. Most dogs don't need to be watched for a few hours, but I can certainly see situations where it could be needed.