This letter thanks a businessperson who recommended a contractor that worked out very well.
1234, Main Street
Boston, MA 02123
<Recipient Address Goes Here>
Just wanted to drop you a line to say thanks! <contractor's first name> was a great suggestion to work on our <brief project description>. <He/She> brought along some great ideas and was wonderful at working with our in-house people! The project came in on time, and everyone was thrilled.
Please let <contractor's first name> know that I will give <him/her> a glowing reference at any time. Thanks again for the assistance!
encl: <List of enclosed items goes here>