In general, most consumer-grade printers are worth next to nothing if used. Companies that manufacture printers make most of their money on ink sales, so they subsidize the cost of the printer itself, making them cheaper to replace. Printers are also prone to mechanical problems, which reduces their value.
Some units command a higher price on the used market. HP LaserJet and Xerox Phaser office printers, for example, are durable and can sell in the $100 to $300 range if they are kept in good condition. When considering buying or selling a used printer, test it fully and ensure there are no malfunctions.