Key easing involves compressing the felt on the piano keys so they move more freely. This is done by removing the key and compressing the key bushing felts then putting the key back in place. Some reasons you may need key easing would be because of piano age, humidity, or poor construction. Most commonly it is due to humidity causing the wood to swell causing the keys to stick and rub on the pins. If this is the cause of your sticking keys this is the easiest problem to fix. For this service, it is $200 and includes easing both the front and balance rail bushings on the key.