[Help] What are the differences and similarities between self-occupied rooms and free rooms?

Private rooms are hotel-operated rooms occupied by senior executives. Generally speaking, the general manager, chairman, and mod may occupy guest rooms. Free rooms are usually temporarily opened to provide housing for suppliers. For example, for a supplier that sells hotel management software, in the past, engineers trained employees, and the hotel usually provided free accommodation. In fact, it would definitely cost more to let the engineers live elsewhere.