Thanks for your question!
This piano was built by Kohler and Campbell in 1904 based on the serial provided. Unfortunately, existing records don't give any additional information on this number besides year built. At this age, I am assuming your piano is a tall upright, likely over 50" tall. This is really the only kind of upright built at the time and the large size allowed for a full sound. Smaller uprights built following the depression are inferior. I'm assuming they left the piano because they realized the value is very low. An old upright in good original condition is only worth a couple hundred dollars. If there are moderate or serious mechanical or cosmetic issues, the value of the piano would likely drop to $0. There's no good answer in restoration, as you'll end up putting more money into the piano than it will sell for, and because so many are on the market, there's no antique value or collector looking for one. Sorry for the bad news but hope this answer gives you some helpful info. Best wishes!
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