Q. How often should a dog come inside the house?

This is a personal choice however, unless you spend loads of hours a day outside with your dog, it is difficult for the dog to learn how your family live in all aspects. Hence it does make sense to bring the dog in for a few hours every day to hang out with the family. Remember that outside space is play space and inside space is chill space. The dog needs to learn how to chill out with the family.