Thank you for your patience.
From the Yamaha serial number listings your piano was built in 1954 so it is over 60 years old. However, the total rebuild/restoration in 1993 will have reset the clock quite considerably. That said, there will be some depreciation from then due to age and usage to consider.
Yamaha have a particularly good reputation for making a very good range of quality pianos and thus their second-hand prices hold up quite well.
From that which I can see in the pictures you attached, the condition is very good and assuming that it has been regularly tuned and maintained, with the information I have, together with the information you have provided, I believe that your Yamaha Baby Grand Piano now has a value in the $6,500 to $8,500 range for a private sale.
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