Thank you for your patience Carolyn
The serial number dates your piano to 1904, so it is around 111 years old. At nearly 57 inches high it is a large upright piano which will have a good strong full sound.
Generally pianos have a limited life span of 60 to 70 years, mainly due to the wear during use and particularly due to the natural deterioration of the major mechanical parts such as the action, the strings, the soundboard, the tuning pins, the pin block, etc., over time. This can be extended by careful regular maintenance/tuning/repairs and some restoration over the years or a total re-build/restoration of the major mechanical components. Thus one of the overriding factors in any appraisal valuation on a piano is the age and condition of the internal mechanics, plus the potential for remaining life without the need for major expenditure to maintain or renew that life.
Based on the information I have, the details that you have provided, the fact that your Adam Schaaf Cabinet Grand Upright Piano has not had any major restoration in at least 40 years and mechanically it is probably as originally built in 1904 save for tunings plus ongoing maintenance, I believe it now has a value for a private sale in the $300 to $600 range. I am sorry that it is not better news but there are still a good many similar pianos around and often for sale.
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