Population density means people build up. Chances are you will not live on the first floor of a building. If you are moving a wardrobe, mattress, refrigerator, washing machine, or other large items, it will be very difficult to bring them up and down stairs. The easiest and cheapest way to move them is via an elevator. While villas will not have an elevator, apartments will. Depending on when the apartment was made, and the rules of the apartment complex, you may or may not be able to use the elevator for your move. Reasons can include inconveniencing other residents for upwards of multiple hours, potential damage to the elevator through scratching and accidental impacts, and maximum size and weight restrictions of the elevator. Simply said, when you are planning your move, you need to contact the building management and clarify whether you can use the elevator or not.
If you are allowed to use an elevator, the moving company will need to line the inside of the elevator to protect it from getting scratched. Some apartments are prepared for people and have custom made padding that can be set up in a minute with magnets. Images of both are below. For more information on elevators in Korea, please see the elevator page.