The earliest player housing in a MMORPG was in Ultima Online which allowed players to own their own houses, which could be decorated and even turned into shops with goods for other players to buy. An early problem with this system was players using rows of housing to wall off sections of the world for private use. This was eventually fixed and the housing system upgraded. From February 2003, players were able to custom design their houses as part of the Age of Shadows expansion.