British David Winston, who was born in Los Angeles but moved to the United Kingdom in his twenties, is auctioning his entire collection of 26 pianos.
He restored the instruments for fifty years, but now thinks it is time to retire.
The collection dates back to the eighteenth century and costs a total of about 250,000 pounds (293,324 euros),
Over the years, Winston amassed a remarkable collection.
These include a piano with folding keys and a piano with two manuals, each on one side of the instrument.
According to the restorer, only fifty copies of this double piano, made by the well-known builder Ignaz Pleyel, exist.
"It's an incredibly fascinating instrument. Instead of two people playing side by side on the same keyboard, the instrument responds to two people at the same time. That makes a big difference."
The price is estimated between 30,000 and 50,000 pounds.
Instrument of the friend of Andy Warhol
There is also an instrument depicting the Polish pianist and former prime minister Jan Paderewski.
It would go out for 6,000 to 8,000 pounds.
And one of the other instruments was once owned by Jed Johnson, artist Andy Warhol's friend, and went on to become the property of the prestigious Forbes Collection.
Its value is estimated at 12,000 to 18,000 pounds.
Winston sells his pianos at British auction house Dreweatts on September 23.
"I want to retire and have an easier life. Working on pianos is physically demanding," he told
"I am also aware that you can never really own these works of art. You take care of them for a while, but at some point you have to pass them on to other people."
Career started as a violin maker
Although he does have some stress before the auction.
"I'm probably going to lock myself in a room that day and ask someone to come get me when it's over."
He keeps one instrument, a harpsichord, to himself.
Winston started his musical career as a violin maker, but did not play the violin himself. "All I could play on the violin was the Mickey Mouse tune," he says. After five years he gave up violin making and trained as a keyboard instrument maker. He built and restored instruments for fifty years - including pianos that have belonged to Beethoven, Chopin and Liszt - and was raised to the British peerage in 2012.