How much is a piano worth?

I remember when an "old" man ("old" as seen/defined by a young child when the person has gray/white hair) would come to tune my piano when I was a young child. He showed up with his dog. The piano tuner was blind.

After tuning the old upright piano he would play several beautiful compositions for us (my mother, my sister, and me). His wife was sighted so she drove him to his tuning appointments. My mother would entertain his wife in the living room while I and my younger sister would sit in the dining room (where the piano was) and be mesmerized by the beautiful music he elicited from that second-hand (or older) upright.

 

My piano teacher's tuner was blind as well.

I remember back when I was about 20, we bought a new piano, (the one we have now) and when I told my teacher this, she said:

"You better buy an antique one. Pre-war".

I asked her why?

She said:

"The best pianos were all made pre-WWII. After WWII, the lumber-stocks which the big piano-makers used, were all destroyed or used by the war-efforts in America and Germany. As a result they had to manufacture post-war pianos using inferior materials and methods - and quality suffered as a result. Pre-war pianos were made the old-fashioned way using dried, aged timber which had been sitting around for decades, so the quality was much higher, since there was less chance of the wood warping, cracking and drying out".

 

I'm fairly certain my childhood "old piano" was "pre-WWII."