 This attributes to the cost of the guitar, where they range from about $2,000 to $4,000 depending on the model you purchase, the twelve-string tends to be one of the most expensive.The creator of RainSong, John Decker designed the guitar, like most inventions, out of the necessity for a product that didn't exist.This idea was sparked when Decker was playing guitar for a wedding in Hawaii when it started to pour.