In reference to your inquiry regarding your Steinway & Sons Cabinet Grand Upright Piano over 50 inches tall, bearing serial number 91008, manufactured in 1898.This piano is an antique. Antiques appreciate in value for reasons of age, craftsmanship. In good condition, the action, strings, keys, pinblock, etc. are in perfect working order some surface scratches, no rust. Any reconditioning should be deducted from the value. The piano is maintained in a normal residential environment. When this instrument is tuned the value is $8,850.00. Based on the age, condition, size, grade and rarity of this piano. This refers to the price that you would need to pay to buy the nearest equivalent to your piano. This is the actual value of your piano as it stands in your living room. This is the amount you want to insure your piano for in case of loss or damage. The amount an insurance company would pay in case of loss.