This grower is sure of this plant identification.
21 foot trachycarpus fortunei. Buyer would need to dig out and collect tree.
Chinese windmill palm, Chusan palm, Palm
Trachycarpus fortunei (Chinese windmill palm). This species of palm reaches about 9m tall, with leaves held on long stalks which are dark green above and blue-green below. The flowers are dense, showy clusters of small yellow flowers which precede the marble-sized, dark blue berries.
They will adapt to any free-draining soil in partial-shade or full sun. You will need to protection from cold winds. Watch out, it is suckering.
Specimen. Interesting leaves, frost resistant