Albert Barnes Commentary 1 Chronicles 19:6

"And when the children of Ammon saw that they had made themselves odious to David, Hanun and the children of Ammon sent a thousand talents of silver to hire them chariots and horsemen out of Mesopotamia, and out of Arammaacah, and out of Zobah." — 1 Chronicles 19:6 (ASV)

A thousand talents of silver - The price is not given in Samuel. On the practice of hiring troops about this time in western Asia, see 1 Kings 15:18; 2 Kings 7:6; 2 Chronicles 25:6.