The NEC requires all single-family and double-family homes to have a 1 receptacle in the front and 1 receptacle in the rear of the house. Additionally “Balconies, decks and porches that are accessible from inside the dwelling unit shall have at least one receptacle outlet installed within the perimeter of the balcony, deck or porch. The receptacle shall not be located more than 6½ feet (2m) above the balcony, deck or porch surface.” However if the area is less than 20 square feet then a receptacle is not required. As an inspector we should be aware that if the home was built before the 2008 requirement, it should not be called out as a defect if a receptacle is missing. However recommending a receptacle be added is appropriate.
The reason for this code change is to prevent fires caused by overloading and short circuiting when using extension cords. GFCI is required.