A customer at the mall is shopping for holiday gifts, and is considering having them wrapped. He can get them wrapped at the department store, which charges $1 per gift. Alternatively, the customer can pay his niece a flat fee of $18 to wrap all of his gifts. If he has a certain number of small packages, it would cost the same amount either way. What would be the total cost to have all the gifts wrapped? How many small gifts would that include?