The relatively low initial investment and ease of resin casting means that it's also easy to create recast copies of existing original kits. Recasts are produced by making molds of parts from original model kits and then doing recasts from the new molds. This can be done for personal use, such as modification of an existing kit, but unlicensed recast copies are sometimes sold unlawfully. In some cases the original kit is no longer available, but in others they are still in active production. The recasts can be of officially licensed model kits, but when they are of unlicensed kits the sculptor usually has a hard time pursuing litigation. The recasts are usually of inferior quality when produced in Thailand, however, other recasters in Hong Kong rival originals in quality and casting and offer at a price that undercuts the original. Recast kits can be found on online auction sites, where they can be difficult to control due to potential cumbersome site policies and seller pseudonymity. Many recasters are in East Asia but can be found all over the globe.