From Nookipedia, the Animal Crossing wiki.
Saharah (ローラン, Rōran, Roland) is a camel in the Animal Crossing series that trades in rare carpets and wallpaper to the player. She has a different service in each Animal Crossing series game. Her name comes from the Sahara Desert in Africa.
In the original Animal Crossing, Saharah makes her living selling rare and exotic carpets from faraway lands. Like most of the game's other special characters, Saharah sells items that cannot be found anywhere else. She does, however, have a different way of doing business than Tom Nook; she accepts trade-ins. In order to get your hands on one of her carpets you must trade in one of your carpets along with some money. Her prices go up each time you buy a carpet and prices can get pretty steep. Don't be stingy because chances are she has the carpet you need to complete a certain series or theme. In the original she also retains her Japanese Male voice.
In Animal Crossing: Wild World, Saharah returns and this time she gives rare wallpaper, taking over for Wendell. Instead of her trade-ins, she asks you to deliver carpet and wallpaper to special characters such as Blathers, the Able Sisters, Tom Nook, Pelly and Phyllis, similar to the way that the player works for Tom Nook earlier in the game. In return, she will give you either rare carpet or wallpaper.
She plays a part in the Golden Axe Trading Event, which involves the player trading various items to other special characters and hopefully get given a Golden Axe. When the player gets to know Saharah, she will talk about how she "longs for a turban". When given a turban, she will either give the player a red vase or a massage chair which can then be used further on in the event, by trading to Tortimer.
In Animal Crossing: City Folk, Saharah returns and once again accepts trade-ins. Though the player does not have to pay, she asks for old wallpaper or carpet from other villagers around town, and only one or two will have them. If you save three of these old wallpapers or carpet every time she visits, she will give you a special gift. If you try to give her a wallpaper or carpet from your home or Tom Nook's Store, she will say that it is "still lovely!" but not accept it.