Interesting situation. The way the dog is raised will determine the answer, not just the breed. If the dog is well socialized and the visitors are introduced to the dog by the owners, there should be no problem. If any of them is afraid of dogs, that will make it more challenging. Worst case, ask the tenant to accompany the dog while it's out in the yard for the duration of your stay. I sincerely doubt that you have a "dangerous' situation, but your concern is legitimate. It all comes down to the owners...