In general, the quickest and most cost-effective way of selling a second hand piano is to place an advert in local newspapers or classifieds, especially online if possible. Online adverts often cost very little in comparison with printed adverts, so they are a better choice.
Using online classifieds generally means that in addition to saving on advertising costs, much larger audiences can be reached. Additionally, an image of the piano can normally be uploaded to classified advert sites, and this can make it much easier to find a buyer, while also showing the instrument's overall condition.
There are additional options to consider. Contacting a local piano technician may result in them taking an instrument for refurbishment. Furthermore, getting an instrument checked over by a technician, and repaired if necessary, can help raise the price of the item by ensuring it is in the best possible condition.
Local music stores that sell pianos may also be interested in second hand purchases. Placing an advert in similar shops can also reach a target audience faster in many cases.
Adding a few extras can make a used piano more appealing. Offering a bench, music stand and other accessories can increase the value of the sale, as well as offering a potential bargain for buyers.