I work in a used good store and we sell a lot on consignment, including a lot of electric guitars. Our standard deal is the consignor sets the price (with some advice from us on the market rates for items) and we split the sales price 50/50. A $300 guitar gets us 150 the guitar owner 150. Most are happy with that. We handle all the merchandising, marketing, selling and money handling as well as taking the risk of keeping and storing the guitar. Most are happy because all they do is drop it off with us and pick up a check when it sells.